Black Eyed Peas singer will.i.am is being investigated by Berlin authorities for his role in a nightclub brawl after a show this week, police said Friday.

Will.i.am -- the group's dreadlocked lead lyricist whose given name is William Adams -- was allegedly part of a fracas that broke out at an after-show party at Berlin's downtown 40seconds club, said police spokesman Ronny Frank.

Details were sketchy, Frank said.

From what police know, at about 1:30 a.m. Thursday a fight broke out between the club's doorman and the group's bodyguard, after the bodyguard tried to prevent photos of the group by shining a flashlight into the lenses of their cameras, Frank said.

"Then a fight broke out, with the doorman on one side and the bodyguard on the other side," Frank said. "A champagne bottle was used, but as far as what the singer did there are various reports that contradict one another, and it's not yet clear what happened."

All three men were taken into temporary custody for statements and contact details, and were then released, Frank said. Police are investigating all on possible charges of causing bodily injury, and causing serious bodily injury.

The names of the doorman and the bodyguard were not released.

Berlin's tabloid B-Z newspaper published graphic photos of the fight on Friday, which show the doorman with blood covering his face grappling with the bodyguard in one frame, then appearing as if he was getting ready to hit the bodyguard with a billy club or similar object in another.

Band member taboo can be seen in one picture watching the two fight, apparently consoling a frightened woman with a hug. Will.i.am is pictured in another, grabbing the arm of an unidentified person.

The newspaper said bandmember apl.de.ap was also at the club, while singer Fergie stayed at her hotel to sign autographs.

According to the paper, the band and its entourage packed the VIP section of the club, but their bodyguard kept waving more people in.

Club manager Torsten Schermall told the newspaper that the fight broke out after his security guard told the bodyguard not to let any more people through.

"He didn't pay any attention," Schermall was quoted as saying.

The newspaper reported the bodyguard hit the security guard with a champagne bottle in the head and "blood flew," then many bottles and glasses were thrown around.

It reported will.i.am threw a beer bottle at the security guard, but did not say who told them.

"It was a witches cauldron," 26-year-old actress Romina di Lella, who was in the VIP area, told the newspaper. "I haven't ever seen anything so brutal. They were at each other for five minutes."

The newspaper reported there was no immediate comment from the Black Eyed Peas, and there was no statement posted on their Web site Friday. The band next plays July 1 in Montreux, Switzerland, and it was not clear where they could be contacted for comment.