Police Searching for Person of Interest in Case of New Hampshire Couple Found Buried on Beach

The unidentified suspect was caught on surveillance video driving the couple's SUV, police said.

Police are searching for a person of interest in the mysterious disappearance of a New Hampshire couple whose bodies were found buried on a remote Texas beach.

James Butler, 48, and his wife, Michelle, 46, had been reported missing for nearly three weeks when their remains were discovered late last month in a shallow grave on Padre Island, along the Texas southern coast, police said.

An unidentified person of interest was captured by a surveillance camera at a check point along the Mexican border, authorities said. He was driving the couple's SUV, police said. 

The bodies were unearthed after investigators detected a ping from one of the couple's cellphones, authorities said. Kleberg County Sheriff's deputies searching the area found a bra covered in sand. After digging below the clothing, two bodies were discovered, authorities said.

Because the remains were badly decomposed, it took medical examiners several days to identify them, officials said.

The causes of death have not been released, but the sheriff's office has classified the case as a double homicide.

Family members said the couple loved to travel and were headed to Florida to sell Christmas trees. 

They were reported missing on Oct. 23, after relatives said they hadn't heard from the husband and wife in a week, which was highly unusual, family members said.