A convicted sex offender was charged Friday with sexually assaulting a 2-year-old girl in a Union City store.

Eugene Melendres Ramos, 36, of Union City was charged with committing a forcible lewd act on a child, assault with intent to commit a sex crime and attempted intercourse or sodomy with a child under 10.

Ramos was convicted in 2005 of sexually assaulting a 7-year-old girl in Hayward.

On Wednesday, Ramos allegedly pinned a 2-year-old girl to the floor in an aisle of the Dollar Tree store at 1720 Decoto Road. The girl's aunt and grandmother had briefly become separated from the girl.

The grandmother turned into the aisle and found Ramos sexually assaulting the girl, police said.

Ramos ran but was tackled outside by two men who saw the two women pursuing him, police said. He is being held at Santa Rita Jail in Dublin.