NEWARK -- A 38-year-old city man admitted in state Superior Court that he robbed the same 7-Eleven three times in a four-day period last December, the Essex County Prosecutor's Office announced Monday.

Idris Allen. (Essex County Prosecutor's Office)

Idris Allen's robbery trial had been scheduled to begin Monday before Judge Verna Leath in Newark, but Allen instead pleaded guilty Friday to first-degree armed robbery, Essex County Assistant Prosecutor Jason Goldberg said in a statement.

Authorities said Allen entered the store, in the 700 block of Broad Street, on Dec. 8, 10 and 11, each time stealing candy and brandishing a knife when confronted by store personnel.

Prosecutors said that when Allen entered the store for a second time on Dec. 11 and again attempted to leave with more merchandise, he was followed by the store manager from the first robbery, who pointed him out to police.

Police arrested Allen across the street from the Newark police precint on Broad Street, where he was trying to discard his clothes, according to prosecutors. Authorities said Allen still had the knife with him at the time of his arrest.

Allen is expected to be sentenced to seven years in state prison, and will have to serve 85 percent of his sentence before he's eligible parole, Goldberg said in the statement.

Allen's sentencing has been scheduled for April 24.

Thomas Moriarty may be reached at tmoriarty@njadvancemedia.com. Follow him on Twitter at @ThomasDMoriarty. Find NJ.com on Facebook.