SAN FRANCISCO (AP) — The suspect in the kidnapping and killing of a central California family was a former employee who had a longstanding dispute with them that “got pretty nasty,” a sheriff said Thursday.

Relatives of the slain family told investigators that Jesus Salgado, 48, had sent angry text messages or emails about a year ago after working with their trucking business, Merced County Sheriff Vern Warnke told The Associated Press.

Salgado alleged kidnapped an 8-month-old baby, her parents and uncle at gunpoint in Merced on Monday and killed them and left their bodies in an almond orchard shortly after, authorities said. The bodies were discovered by a farm worker late Wednesday in the remote area near the town of Dos Palos, about 30 miles (50 kilometers) south of Merced.

Investigators are also seeking a person of interest who may have acted as Salgado’s accomplice, the sheriff said.

Warnke said he believed the family — 8-month-old Aroohi Dheri; her mother Jasleen Kaur, 27; father Jasdeep Singh, 36; and uncle Amandeep Singh, 39 — was killed before their relatives reported them missing Monday.

Authorities said the abductor was a convicted robber who tried to kill himself a day after the kidnappings. Salgado was in critical condition when taken into custody but has been talking to police, Warnke said.

“There’s no words right now to describe the anger I feel and the senselessness of this incident,” Warnke said. “I have said it before, there’s a special place in hell for this guy.”

The four family members were taken from their business in Merced, a city of 86,000 people about 125 miles (200 kilometers) southeast of San Francisco in the San Joaquin Valley, California’s agricultural heartland.

The released surveillance video showed the suspect first walking by the property before talking to one of the men. Later, it shows him leading the men, who had their hands zip-tied behind their backs, into the back seat of Amandeep Singh’s pickup truck. The suspect then went back to the trailer that served as the business office and led Jasleen Kaur, who was carrying her baby in her arms, out and into the truck before the suspect drove them away.

Family members said nothing was stolen from the trucking company but that their relatives were all wearing jewelry. Warnke had said that after the kidnappings, an ATM card belonging to one of the victims was used in Atwater, about 9 miles (14 kilometers) north of Merced.

Public records show the family owns Unison Trucking Inc. and family members said they had opened an office in the last few weeks in a parking lot the Singh brothers also operated. Authorities said they were taken from their office.

The victims were Punjabi Sikhs, a community in central California that has a significant presence in the trucking business with many of them driving trucks, owning trucking companies or other businesses associated with trucking.

Family members on Wednesday asked owners of stores or gas station in the area to check their surveillance cameras for images of the suspect or those missing.

“Please help us out, come forward, so my family comes home safe,” Sukhdeep Singh, a brother of the victims, said, his voice breaking.

Relatives of Salgado contacted authorities and told them he had admitted to them his involvement in the kidnapping, Warnke told KFSN-TV on Tuesday. Salgado tried to take his own life before police arrived at a home in nearby Atwater. He has since been hospitalized.

Efforts to reach Salgado’s family were unsuccessful Thursday.

Salgado was previously convicted of first-degree robbery with the use of a firearm in Merced County, attempted false imprisonment and an attempt to prevent or dissuade a victim or witness. Sentenced to 11 years in state prison in that cae, he was released in 2015 and discharged from parole three years later, according to the California Department of Corrections and Rehabilitation. He also has a conviction for possession of a controlled substance, the department said.

The sheriff said detectives believe the kidnapper destroyed unspecified evidence in an attempt to cover his tracks.

The sheriff’s office said firefighters on Monday found Amandeep Singh’s truck on fire. Merced Police Department officers went to Amandeep Singh’s home, where a family member tried to reach him and the couple. When they were not able to reach their family members, they called the Merced County Sheriff’s office to report them missing, the office said.