Nassau County Police Dept.(NEW YORK) — A Long Island woman whose boyfriend locked her and her three sons in a car was freed after she held a “CALL 911” sign on the car window, leading to their rescue, according to authorities.

William Jamal Wilkinson, 35, was driving on Long Island, N.Y., Tuesday when he refused to let his girlfriend and her children — a 13-year-old boy and twin 3-year-old boys — out of the car, allegedly holding them with threats of violence, according to court documents.

After pulling into a gas station, the woman was able to get a passerby’s attention by pressing a note against the window asking for help, according to court documents.

A witness alerted authorities after seeing the woman in the front passenger seat holding a sign that read “Please call 911, CALL 911,” according to Nassau County police.

Wilkinson, of Ridge, N.Y., was arrested on charges including unlawful imprisonment, according to police.

The children are not Wilkinson’s, according to the Nassau County District Attorney’s Office.

A potential motive was not immediately clear.

Wilkinson was arraigned on Wednesday and is due to return to court on Friday, according to prosecutors.

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