NEWARK - An investigation is underway into a fatal accident on the Garden State Parkway that claimed the life of a New York woman Tuesday night.

Authorities say 39-year-old Velma Castro, of Spring Valley, was killed instantly after the church van she, her husband and 20 others were taking to a bible study in Newark suddenly collided with an off-duty New Jersey Transit bus near the exit 159 ramp.

Four others, including Castro's husband, were seriously injured in the crash and are being treated at St. Joseph’s Regional Medical Center.

Police are investigating whether the Ford Econoline van was carrying too many people when it allegedly veered into the bus. Pastor David Castillo, of Ministerial Bethel International in Newark, says the van is owned by the church. He guessed that it should not hold more than 17 people.

Castillo says the couple's four children live in Guatemala.

NJ Transit says its bus driver has been with them since 1999 and has an unblemished driving record.