The border guards reportedly spotted the motor boat of the three men--there is no mention of any dog--crossing the temporary control line between Estonia and Russia at 7:42 p.m. on July 9.
The Russian officials detained the three Latvian citizens in the boat on Lake Lämmijärv moving towards the Russian side.
They were reportedly drunk and did not carry identification, spokespeople for the South prefecture of the Estonian Police and Border Guard said.
An Estonian border patrol received the three men, aged 23, 33, and 35 from their Russian colleagues on July 10.