PHOENIX -- Former Detroit Pistons center Bison Dele and his girlfriend were reported missing during a boating trip in the Pacific Ocean, the woman's stepfather said Monday.

	Bison Dele, formerly known as Brian Williams, played for four different NBA teams.

Relatives last heard from Dele, girlfriend Serena Karlan and three members of Dele's boat crew two months ago, said Karlan's stepfather, Scott Ohlgren of Boulder, Colo.

Dele's boat was scheduled to sail from Moorea, Tahiti, to Honolulu and was last reported as being seen near Tahiti, Ohlgren said.

Dele, formerly known as Brian Williams, played on the Chicago Bulls' championship team in 1996-97. He later signed with the Pistons, where he played for two seasons before retiring. He played at Arizona in 1990 and 1991.

Before his disappearance, Dele had contacted his bank once a month. The bank hasn't heard from Dele in two months, Ohlgren said.

Dwight Manley, Dele's agent in Los Angeles, said he last spoke with Dele four months ago.

''I don't think that he would just stop communicating with his family and his banker and his best friends.''

Karlan, who started dating Dele in January, usually called her mother once a week, Ohlgren said.

''Like clockwork,'' he said. ''This is a woman who is connected to her mom at the hip. It was very unusual that we didn't hear from her.''

Ohlgren said missing persons complaints were made in Colorado and Michigan, where Dele had business contacts.

Police in both states said Monday night that no missing persons cases under those names could be immediately found.

The FBI doesn't handle missing persons cases but was still monitoring developments, said Susan Herskovits, a spokeswoman for the agency's Phoenix office.

Phoenix police, meanwhile, investigated a possible identity theft case last week involving a man claiming to be Brian Williams.

A coin dealer tipped off investigators that the man, whose identity wasn't released by police, was seeking to pay money for gold bullion, said Phoenix Detective Tony Morales.

The coin dealer had questions about the transaction and learned that Dele was reported missing, Morales said. The man presented identification and presented himself as Brian Williams but he wasn't in fact Williams.

The man was released after detectives interviewed him.

''He is nothing other than an investigative lead and a possible identity theft case,'' Morales said.

While Phoenix detectives aren't investigating the missing persons case, they were concerned about the identity theft allegation, Morales said.

''You have a person who was reported missing and then you have someone showing up reporting to be that person,'' Morales said.