Two of four US citizens kidnapped in Mexico found dead

Two of the four US citizens kidnapped after crossing over the border into northeastern Mexico have been found dead, a senior Mexican official said Tuesday.

The attorney general's office confirmed that of the four abductees "two of them are dead, one person is injured and the other is alive," Tamaulipas state governor Americo Villarreal told a news conference by telephone.

A Mexican national was also killed in the incident.

The US citizens crossed into Matamoros, in Tamaulipas state, on Friday in a white minivan with North Carolina license plates, the US Federal Bureau of Investigation (FBI) said in a statement released on Sunday.

It offered a $50,000 reward for help leading to the return of the unidentified victims and the arrest of the perpetrators.

"Shortly after crossing into Mexico, unidentified gunmen fired upon the passengers in the (minivan). All four Americans were placed in a vehicle and taken from the scene by armed men," the FBI said.

Mexican President Andres Manuel Lopez Obrador said on Monday that the victims were believed to have entered the country to buy medicines and got caught up in a confrontation between criminal groups.

Matamoros, located across the US border from Brownsville, Texas, has been beset by violence linked to drug trafficking and other organized crime.

The US State Department advises against travel to Tamaulipas due to crime and kidnapping.

In a separate statement, the White House denounced the kidnapping and murders, as "unacceptable," and said Washington would pursue justice for the victims.

"We're going to work closely with the Mexican government to ensure that justice is done in this case," White House national security spokesman John Kirby told reporters.

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