Algeria's defence ministry was quoted as saying that 247 passengers and 10 crew members were among the dead following the crash.
Ennahar TV quoted an Algerian ruling party official as saying that 26 people onboard were members of the Polisario Front, a separatist movement in West Sahara - a territory also claimed by Morocco.
Algerie24, a local news website, said the plane was heading to the western Algerian city of Bechar.
Images posted on an Algerian website showed thick smoke billowing from the site of the crash, as several people rushed to help.
The crash at Boufarik would be the worst in Algeria since 2003 when an Air Algerie jet crashed shortly after takeoff from Tamanrasset, killing 102 people.