Police in Lurgan have come under what they have called a sustained attack from youths throwing petrol bombs and other missiles.
Army bomb disposal experts examined part of the railway line
Up to 30 petrol bombs were thrown by a crowd of about 20 youths in the Cornakinnegar Road area.
Police were in the area while Army bomb disposal experts examined a device on the railway line. It has been declared a hoax.
Earlier two petrol bombs were thrown at a BBC television crew in the town.
The crew were at the Kilwilkie estate when the devices were thrown at their car. No-one was injured but one device hit their vehicle.
The railway line between Lisburn and Portadown has now reopened.
It had been closed after workmen discovered a suspicious object on Monday close to Malone Bridge on the Lurgan side of Bells Bridge.
SDLP Assembly member Dolores Kelly claimed dissident republicans were training young people to leave devices.
"Local people reported to us seeing young people being almost trained in paramilitary fashion to leave the device and wearing balaclavas," she said.
"So, it seems as if there is an element of recruitment amongst dissident republicans training young people, or at least corrupting their lives, and disrupting the lives of everybody else around them."
She said hoax devices were often left as a means of luring security forces into the area, to be attacked.
Ms Kelly also condemned the disruption caused by such incidents to every day life.
"There is not easy transport access outside of Lurgan other than the train and it is widely used," she said.