What we know about the Americans kidnapped in Mexico

Four U.S. citizens were kidnapped in a brazen attack carried out by multiple gunmen in the northern Mexico border city of Matamoros, the FBI said. 

U.S. officials confirmed on Monday that a Mexican citizen was killed in the incident.

The Americans traveled to Matamoros, in Tamaulipas state, across from Brownsville, Texas, on Friday in a white minivan with North Carolina license plates.