FRANKFURT, Germany (AP) _ Police today identified the woman who killed herself and two others by detonating hand grenades at a Christmas Eve service as a 49-year-old who had been receiving psychiatric treatment.

The woman lived in Usingen, near Frankfurt, and had been separated from her husband for a year, according to police spokesman Manfred Fuellhardt.

He did not specify what sort of care she had been receiving and said, ``We still don't know what led her to do this.''

Police refused to release the woman's name, saying they wanted to protect any relatives from publicity. The woman had a 9-year-old daughter, who lives with her estranged husband.

The woman detonated two grenades inside Lutheran Church Sindlingen-South, in a working-class neighborhood of western Frankfurt. The grenades were concealed under her cape as 70 worshipers began singing the first hymn of the late service.

Two women next to her, 59- and 61-year-old sisters, were killed. Ten people were hospitalized, two with serious head injuries. Police said the 12-year-old girl was improving today; her mother remained critical.

The bomber apparently picked the church at random, police said. However, her family had lived in the Sindlingen neighborhood until the end of 1980s.

Police said they had no evidence suggesting a terrorist act, and suspected she wanted to kill herself in a spectacular way.

The bomber was identified by people who recognized her from photographs released by police after the blast. Although her lower body was blown up, the woman's head had remained intact.

Most of the worshipers knew each other well and many were coworkers at the nearby Hoechst chemical plant.

They held a special Christmas service today at another Lutheran church in the neighborhood. A memorial service also was planned for Sunday at the St. Dionysius Catholic Church.