SEATTLE – Police are searching for a man who is sexually attacking women at South Seattle bus stops.

Police say the man has already assaulted four women and it appears the suspect is becoming more aggressive and violent.

The attacks started a little over a week ago. They have occurred along Beacon Avenue South from Columbia to South Cloverdale in the vicinity of 45th Avenue South and 36th. Most have happened between 5:30 p.m. and 9:45 p.m. although some have happened in the morning between 8:30 a.m. and 10 a.m.

All of the attacks have happened along sidewalks and all of the victims were Asian American. Police fear the man is growing bolder by the day

"He is actually physically pulling these women to the ground and is attempting to grab them on areas on their bodies, whereas in the first attacks he was just touching them," said Renee Witt, Seattle police spokesperson.

Victims have only been able to provide this vague description of the suspect. They say he is a black man in his late teens to early 30s, wearing a grey hoodie and a hooded coat and jeans.

Police say they don't have much to go on, but they do have one important clue - the attacker may be riding the bus himself

"A majority of the attacks are within close proximity to Metro bus shelters … route 32 and 36," Witt said.

Seattle police are working with Metro buses, but they say women need to watch out for their safety..,

Police also believe there may be even more victims and detectives are asking them to come forward.