Hicks, who has starred in "Zeke and Luther," "Pair of Kings" and "Lemonade Mouth" allegedly committed 4 or 5 armed robberies ... this according to law enforcement sources.

Our sources say 25-year-old Hicks and his girlfriend would go up to people walking in the San Fernando Valley area, stick a gun in their face and demand money, cellphones and other items.

We're told 2 of the victims are elderly women in their 70's.

SWAT went to a home Wednesday afternoon where Hicks was staying and arrested him for armed robbery.

We've learned Hicks has 2 prior arrests on his record, both last year in Los Angeles.

In July, he was busted for firing a gun, and in September for a battery. The D.A. rejected both cases for insufficient evidence.