Several subway lines saw suspensions and severe delays Thursday as police investigated a shooting that happened on the Upper West Side, officials said.

Police said a suspect opened fire at a 47-year-old man at West 68th Street and Columbus Avenue around 9:20 a.m.

The victim, who was shot in the shoulder and leg, was taken to a nearby hospital, where he was expected to survive, the NYPD said.

The NYPD said police believe the gunman fled into the nearby 72nd Street subway station, setting off a cascade of suspensions and other service disruptions along multiple train lines for over an hour.

An MTA spokesperson said southbound B and C train service was fully suspended from 10:15 a.m. to around 11 a.m. due to the investigation. By noon, A, B, C and D trains were still running with severe delays in both directions, the agency said. 

Regular service along those lines had resumed by mid-afternoon, the MTA said. 

Police said the search for the suspect remains ongoing.