A Pennsylvania police officer is in critical but stable condition after being shot, while a three-hour manhunt ended with at least one person in custody.
Train service has meanwhile resumed in the area just south of Philadelphia.
Authorities say 25-year-old Folcroft Officer Christopher Dorman was shot several times Friday morning while investigating reports of drug use behind an apartment house.
Folcroft Chief Robert Ruskowski says Dorman was conscious when he was admitted to the hospital and is preparing to undergo a second surgery.
He says the officer's bulletproof vest may have saved his life.
An Amtrak spokesman says about a dozen trains were affected when tracks in the Folsom area were closed for more than two hours. A commuter train line that uses the same tracks was also affected.