Eight shootings in Chicago have injured 19 people, as violence continues to rise in the midwestern US city.

The spate of shootings late on Thursday night and early on Friday brought the number of murders in Chicago this year to 340, according to the local Red Eye newspaper.

In the previous year, police reported 433 homicides.

The vast majority of the recent shootings have been in the city's troubled south and west sides.

The bulk of the bloodshed on Thursday occurred in the early evening when 13 people were shot in 30 minutes in three separate incidents. 

"It looks like officers were in the area when they heard the gunshots and came upon the scene," Chicago police public affairs officer Jose Estrade told AFP news agency.

"Right now there's nobody in custody, it's an ongoing investigation," Estrade said.