OAKLAND -- Police late Friday were investigating four homicides that occurred hours apart on different ends of the city.

The four killings Friday brought the homicide tally for the year to six, police said -- all of them coming this week.

A woman walking her dog at Canon Avenue and Wellington Street, next to Dimond Park, found a man dead on the sidewalk about 3 p.m. He had been shot, but there is speculation that he was killed in another location and his body dumped there, police said. Neighbors did not report hearing gunshots.

Police identified the victim late Friday as Larry D. Lovett, 30, of Stockton.

A 22-year-old man shot multiple times while in the 2300 block of East 17th Street in the Fruitvale district about 2:30 p.m. died later Friday, police said. His name was not released pending notification of family.

At 4:15 p.m., a man driving a car was shot multiple times while in the 3400 block of West Street in West Oakland. Oakland resident Eddiebo Rodriguez, 20, was pronounced dead at Highland Hospital at 5:26 p.m.

No one else was injured in that shooting, although a few homes in the area were hit by bullets, police said.

At 8:15 p.m., police received multiple reports of shots fired in the 9400 block of Hillside Street. When police arrived, they found a man in the home who had suffered a fatal gunshot wound, according to Oakland police spokeswoman Officer Johnna Watson. He was pronounced dead at the scene.

Information on that case was still developing late Friday and the victim's name was not immediately available.

Police did not know if any of the shootings were related. But even for Oakland, where 131 people died violently last year, four homicides in one day is rare.

Police had not made any arrests in any of Friday's killings and motives were not yet known.

The first homicide of the year was 17-year-old Tyronta Mickens, of Oakland, who was shot multiple times at 12:47 p.m. Monday while sitting in a car in a parking lot at Hegenberger Road and Hamilton Street.

The second homicide of the year was Wednesday, when 20-year-old Malik Birchett, of Oakland, was shot at 2:30 p.m. while in a car parked in the 600 block of 55th Street.

A reward of $10,000 is being offered for any information leading to the suspect or suspects in all of the killings. Anyone with information can contact police at 510-238-3821 or Crime Stoppers at 510-777-8572 or 510-777-3211.

Contact Kristin J. Bender at kbender@bayareanewsgroup.com. Follow her at Twitter.com/kjbender. Contact Katie Nelson at 925-945-4780 or follow her at Twitter.com/katienelson210.