Police said the attack was reported to them in the early hours of Sunday morning, while simultaneously noting that the organizers of the 'People of Maidan' exhibition had failed to provide any security at the central Riga site for two days running, despite assuring police that they would do so.
"In accordance with the Public Entertainment and Festive Event Safety Act, the organizer must provide public security measures but in fact security was not assured. Both last night when the attack took place and the night previously, police found that there was not any actual site security. In the past, the police repeatedly stated the need to ensure security and had received promises from the organizers that it would be provided," said police.
Organizers have yet to explain why they left the exhibition unattended.
Police have appealed for any witnesses to the attack to contact them.
Melnikoff told LSM's Russian language service he would re-open the exhibit at the iconic Freedom Monument.
Riga City Council is understood to be awaiting a view from the Security Police on Melnikoff's controversial views while it mulls whether to take any action.
The Latvian Ministry of Foreign Affairs (MFA) on Saturday attempted to distance itself from the controversial photographer, despite having its crest plastered all over his exhibition and linked websites.
"The MFA indicates that the photos displayed at the exhibition are high quality and the subject matter is serious. At the same time the Foreign Ministry distances itself from the exhibition organizers' statements of an extreme nature, if any, and categorically condemns them," MFA spokesman Raimonds Jansons told the BNS newswire.
"We support the spirit and nature of the exhibition," said Jansons.
LSM canvassed the opinions of experienced professional photographers about the quality of Melnikoff's images both in the exhibition and on his personal website.
Sadly, the latest incident at the exhibition site prevented scrutiny of all the Maidan pictures up close, but an international press photographer with more than 25 years' experience who spoke to LSM on condition of anonymity said:
"I never heard about this guy. And his website is full of images we call 'sandwiches' - layer over layer."
"Whoever designed the website is clever. You can't download the images as jpeg. It's only in HTML. It means that we can't make a search in Google Images or pro searches to find the photographer. The images have a history encrusted (exif) and other parameters," the photographer said.
During a previous controversy involving Melnikoff in Kyrgyzstan, he was accused of passing off as his own photographs from Chechnya by Russian photographer Natalya Medvedev.
There are currently no grounds to doubt Mr Melnikoff's claim to copyright on the Maidan images.
In a further twist, LSM has obtained court documents dating from September 2014 which show Melnikoff may have had more than one reason to be in Kyiv.
Broward County, Florida documents show attempts to serve one "Sergei Melnikov" - at Melnikoff's home address in Florida - with a court order obtained by Discover Bank for non-payment of a credit card debt of more than $6,000.
"Padina Melnikov says she is his wife. He no longer lives here. They are separated. He left two years ago in August and she has not seen him since. She believes he is out of the country," the report by lawyers attempting to collect the debt declares.
If the Sergei Melnikov mentioned is indeed Sergey Melnikoff, it would be embarrassing given the fact his website claims credit card companies use his images on their cards.
One final odd fact about Mr Melnikoff is that his biography says he was a "U.S. asylum grantee in 1990 by personal authorization of President Ronald Reagan."
Ronald Reagan's term as President of the United States ended in 1989.
Latvian Website, Russian Link
In a parallel development, enquiries by LSM's Russian language service have revealed startling new information about a "patriotic" fund named the Latvian Renaissance Foundation which is organizing the exhibition on behalf of Mr Melnikoff, and an extremist "news" site called IPV News owned by the photographer - plus another connection to the Latvian Ministry of Foreign Affairs.
Publicly available records show that ipvnews.org is arguably as much a Latvian as a US resource.
As LSM's Russian-language website found out, the domain of the website was registered by Sergey Melnikoff, as shown in whois records available publicly.
However the phone contact for the domain is Latvian cellular phone number +371 25453827 and tech support provided by Nano IT - a Latvian company.
Records of another Web registry,whoismyisp.com, indicate that ipvnews.org is hosted in Latvia and is supported by Nano IT.
Checking public resources for the aforementioned Latvian phone number ended with a list of foreign correspondents accredited by the Foreign Ministry of Latvia in the year of 2014. the list is publicly available at the web site of the Foreign Ministry.
The number was listed for one Mikhail Alekseev, accredited by "MAYDAYCO News Agency". He shares a surname with the head of the LRF, Sergey Alekseev, though as it is a common surname it may be a coincidence.
Rather, very much along with its name, it appears to a "matchmaking" consultancy, offering the whole spectrum of services from PR and website promotion to "tax planning" and conducting all types of errands in the Baltics (including tour reservation and purchase of real estate and businesses).
MayDay Consulting also has several affiliated projects with expertiza.lv being one of them. Currently the page is busily promoting Melnikoff's Maidan exhibition in Riga.
In quieter times, as already reported by lsm.lv, expertiza.lv promotes investment and visa services for the Russian-reading clientele interested in Latvia and works in tandem with www.latvija-fonds.ru.
The latter web-address links directly to the page of the Latvia Renaissance Foundation. Records of the Corporate Register of Latvia shows that one Mikhail Alekseev (citizen of Russian Federation born in 1984) is a co-founder of Latvia Renaissance Foundation (incorporated in 2013 as a non-profit association) with the full rights to represent the entity in all circumstances.
Records of the State Revenue Service show that in the year 2014 Latvia Renaissance Foundation filed papers with the tax authority requesting the status of a public benefit organization. Taxmen were not convinced: Latvia Renaissance Foundation is not to be found in the Register of charities run by State Revenue Service.
Obviously, Latvian Renaissance Foundation is not enjoying the special tax regime established for charities which would make it hard to provide income tax rebates and other perks for corporate or private donors — despite promising exactly these on its webpage as the "patriotic" tax burden decrease program.
The callousness of the taxmen possibly is the reason why for the whole year of 2014 the foundation received a single donation of €1187 from an anonymous well-wisher.
Just €180 remained unspent the end of 2014 fiscal year. No other revenues are mentioned in the year-end financial report of the foundation seen by Rus.lsm.lv
Nevertheless flyers handed out at the Melnikoff exhibition urge visitors to "donate" to both the Latvian Renaissance Foundation and Melnikoff's 'Soul of Ukraine' Foundation.
Unfortunately for a "patriotic" Latvian organization, the word for donate, "ziedot" is mis-spelled on the flyer as "zedot". The LRF holds its account at Ukraine-owned PrivatBank.