Thirty-seven drivers were arrested Saturday night and early yesterday morning at the third drunken driving checkpoint set up by District of Columbia police on the eastbound lanes of the Southeast Freeway near the Pennsylvania Avenue exit.

About 800 cars were stopped at the roadblock, which was operated from 10 p.m. to 6 a.m. Police said the arrests were routine and there were no incidents.

The number of drivers charged with drunken driving was comparable to previous District roadblock operations. Last month, a Canal Road checkpoint in Georgetown resulted in 39 arrests. The New York Avenue checkpoint in June resulted in 43 arrests.

All three were conducted in the late night and early morning weekend hours, which police say are prime times for drunken driving.

Penalties for a first offense can range up to $300 in fines and 90 days in jail.

The roadblocks were initiated by District police in the summer as part of an intensified effort to curb the sharp increase in alcohol-related fatalities.

They are similar to the "sobriety roadblocks" set up in Maryland and Virginia last year during the Christmas holidays.

In the District, the checkpoints have stirred protests from some motorists--who say that the roadblocks are unfair--and have prompted an effort to place an anti-roadblock initiative on the ballot in November.

The D.C. Board of Elections and Ethics has given preliminary approval to the petition drive for the initiative, which, if approved, would prohibit District police from setting up checkpoints without probable cause or search warrants.