WASHINGTON — In an unusual step, the US Attorney’s Office for the District of Columbia has issued an indictment for the DNA profile of a still-unidentified man linked to a string of rapes in area hotels dating back to 2002.

Police have yet to determine the man’s identity, but law enforcement agencies are hoping to break the case by making their investigation public. The FBI and multiple Washington, DC-area police departments announced Tuesday that the man is suspected of committing at least six sexual assaults and could be responsible for many more.

In a joint news conference, the FBI’s Washington field office along with Washington’s Metropolitan Police Department and police forces from neighboring Maryland and Virginia said that six rapes between May 2002 and June 2003 had been “definitively linked by DNA” to one individual.

Most of the victims were hotel housekeepers attacked while cleaning rooms.

Authorities released a composite sketch of the suspect that was based on DNA modeling rather than eyewitness descriptions. They also released images of a box cutter and a ring that were left by the attacker at different crime scenes.

“DNA evidence has enabled us to push this case forward and we are hopeful that this DNA profile, and the community, can help us finally achieve justice,” said US Attorney Jessie Liu. “Despite the passage of time, we have never forgotten these victims.”

The same man is suspected of involvement in at least three other sexual assaults as recently as February 2006 and a string of attempted break-ins at area hotels.

Metropolitan Police Department Chief Peter Newsham said the suspect has “preyed on members of the D.C. region for nearly a decade.”