Kevin Justin McGuigan, 21, has been charged in the fatal stabbing of his mother outside a Rockville church. (Montgomery County Police)

A 21-year-old man has been arrested in the stabbing death of his mother Friday in front of a Catholic church in Rockville, according to Montgomery County police.

Kevin Justin McGuigan was taken into custody around 7 a.m. Saturday at a gas station and charged with the first-degree murder of his mother, Jaclyn McGuigan, 49, of Rockville.

Witnesses told police they heard screaming Friday in front of the St. Raphael Catholic Church and School on Dunster Road and saw McGuigan standing over his mother, who was lying on the ground near a church entrance. Witnesses said he left in his mother’s Honda sedan.

Police arrived around 6 p.m. Witnesses, officers and fire and rescue personnel attempted to save the woman, but she died at the scene.

Almost an hour later, police found the abandoned Honda at Fallsgrove Park about four miles away. The vehicle had some of the son’s belongings in it.

Police said their investigation so far showed that Jaclyn McGuigan was last seen leaving her Rockville home in the Honda with her son around 5:30 p.m. Friday.

McGuigan was taken to the police’s central processing unit pending a hearing.

Family members had no comment Saturday, but the death left the church community shaken. The St. Raphael School, which is located on the site of the church, tweeted that “we are aware of a fatal stabbing outside St. Raphael’s.”

The message asked for prayers for the victim and her family.

The church and school are about a half-mile north of Montrose Road in southwestern Rockville.