DEDHAM, Mass. (AP) — Prosecutors in Massachusetts say a man ran over his ex-wife four times in the driveway of their Quincy home, killing her, after they fought over his alleged gambling last year.

Yan Long Chow pleaded not guilty Thursday in Norfolk Superior Court to first-degree murder. He was ordered held without bail.

Prosecutors say Chow had told police he accidentally hit Zhen Li in the driveway on Sept. 2. The 52-year-old Li died at the scene.

Court documents say investigators learned the couple often fought over Chow’s gambling.

Chow’s layer, Scott Martin, tells The Boston Globe his 55-year-old client had nothing to gain from Li’s death.

Martin says Chow and Li married in 1985, divorced in 1993, remarried in 1998 and divorced again in 2005, but remained a couple.Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.