OAKLAND -- A woman was stabbed to death and two men were fatally shot within 90 minutes early Friday in different parts of the city, police said.

The three killings bring the number of homicides in Oakland this year to 130, the highest number since 148 people were killed in 2006.

The woman was found fatally stabbed about 2:30 a.m. Friday in a second-floor unit at an apartment house at 5800 Walnut St. in East Oakland. Police were not sure if she lived there and are trying to identify her.

A man at the complex, who had cuts to his hands, was arrested Friday in connection with the woman's death after being interviewed by investigators. Police did not say if he knew the woman or what their relationship was.

His name was not released.

At 1:04 a.m. two men were shot to death in the 800 block of Mead Avenue near Market Street in West Oakland.

They were identified as Darrell Armstrong, 21, who lived in the area where the shooting took place, and Keith Davis, 19, of El Sobrante. Police said the two were friends, but they don't have a motive for the killing.

Police said they were not yet sure if the two were shot by someone on the street or in a car.

The area where the shooting happened is known for gang and drug activity, but police said it was too early to say if those were motives for the killings.

There were two possible drug-related homicides on Mead Avenue in February of 2010 and March of 2010. A 5-year-old girl was hit in the back by an errant bullet that went through a wall of her Mead Avenue home in November of 2009. Police said the bullet was from an exchange of gunfire between drug dealers on the street outside her home.