An arrest warrant was issued Tuesday in connection with the murders of a New Hampshire couple whose bodies turned up in a shallow grave on a Texas beach last week.

Anthony Curtis Williams, 33, was being sought for the theft of the murdered couple’s pickup and RV, Kleberg County Sheriff Richard Kirkpatrick said. The bodies of James and Michelle Butler were unearthed on Padre Island, near Corpus Christi. Their pickup and RV were stolen and driven to Mexico, investigators said.

Kirkpatrick also said a woman was being sought as a person of interest. He identified her as Amanda Noverr, 32.

"We believe these individuals may have absconded to Mexico," Kirkpatrick said. He said his office was working with Mexican investigators to find the couple.

The sheriff described Williams, who had a number of tattoos, as "armed and dangerous."

NEW HAMPSHIRE COUPLE FOUND DEAD IN TEXAS: 2 PERSONS OF INTEREST SOUGHT

He said Williams and Noverr were from Utah. He said he didn’t know what their relationship was.

Investigators on Monday released a photo of Williams and Noverr in the Butlers' pickup crossing into Mexico at the Texas border on Oct. 21.

TEXAS DEPUTIES SAY MISSING NEW HAMPSHIRE COUPLE WAS MURDERED, RV STOLEN

Tipsters who saw the photo provided information that led to their identities, Kirkpatrick said.

Investigators haven't said exactly how the Butlers were killed.

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They were last seen in Texas on Oct. 15. Family reported them missing eight days later after they missed a scheduled call.

Butler, 48, and his wife, 46, were from Rumney, N.H., and had been living in the RV for the past 18 months as they traveled the U.S.