MOSCOW - At least seven people died on Sunday when a riverboat collided with a barge and sank in the Moscow River, Interfax reported, citing an Emergencies Ministry spokesman.

The private boat carrying 16 people sank after colliding with the river barge at around 1 am (2100 GMT). Russian media

quoted passengers as saying the boat had been rented for a birthday celebration.

A string of transport disasters ahead of parliamentary elections in December and presidential polls in March has led President Dmitry Medvedev and Prime Minister Vladimir Putin to condemn the state of the country's infrastructure and endemic regulatory corner cutting.

Survivors wrapped in brown blankets huddled on the river's grassy bank watching Emergencies Ministry boats and divers searching for victims.

"We managed to save seven people. According to preliminary data of the Investigative Committee, there were 16 people on the ship. The fate of two is still unclear," the ministry spokesman said.

Russia 24 quoted witnesses as saying the riverboat was moving erratically on a 200 metre-wide bend in the river before it collided with the barge in southwest Moscow, near Luzhniki Stadium, the site of the 1980 Summer Olympics.