CHICAGO —  An outburst of gunfire rattled the city during the weekend, with at least nine people killed in 36 separate acts of violence.

The shootings were reported from Friday until Monday morning, police spokeswoman Monique Bond said Monday. They included gang shootings, drive-by attacks, and even one case in which someone used an AK-47 to shoot up a plumbing supply store.

Then on Monday evening, a man was shot to death and three other people were wounded in a robbery attempt at a McDonald's, police said.

Authorities did not immediately say whether any of the weekend shootings were thought to be related.

Police Superintendent Jody Weis blamed an excess of guns and gangs.

"There are just too many weapons here," Weis said Sunday. "Too many guns, too many gangs."

During the same weekend last year, there were 19 shootings, including four homicides, and 21 shootings were reported during the same weekend in 2006, police statistics show.

New police data released Saturday showed Chicago's murder rate for March was down about 1 percent from March 2007.