A Herndon man was arrested Monday for allegedly impersonating a police officer and sexually assaulting two women in separate incidents earlier this month, police said.

Thomas C. Kim, 31, used the same technique in both assaults and there could be additional victims, who have not reported crimes yet, said Lt. Jeff Coulter, a spokesman for the Herndon police.

Kim allegedly approached both women on Oct. 11, flashed a badge and began questioning them. He then frisked them and allegedly fondled them in the process, Coulter said. The first attack occurred in the 1200 block of Magnolia Lane around 3:45 p.m., while the second happened in the 400 block of Elden Street at about 7 p.m.

In the second incident, Kim forced the victim into a car, drove her a few blocks and then sexually assaulted her again, Coulter said.

Based on a tip, police began watching Kim and he was arrested on Oct. 24 as he was attempting to assault another woman, police said.

Coulter said the investigation found Kim had approached women at least eight times between Oct. 11 and Oct. 24 in the Herndon area, and sexual assaults were reported in two instances.

Kim has been charged with sexual assault, abduction, impersonating a law enforcement officer and use of a firearm in commission of a felony.

Anyone with additional information about additional assaults is asked to call the Herndon Police Department at (703) 435-6846.