The incidences began just after 7pm when three masked men commandeered a bus at the Drumbeg roundabout in Craigavon. Passengers on the bus were ordered off by the gang.
Around 45 minutes later a van was hijacked on the nearby Old Portadown Road outside Lurgan. Youths who congregated at the area then pelted emergency services with stones and other missiles.
Police remained at the scene in an effort to restore calm. They advised motorists to avoid the area.