An explosion in a pickup truck has wounded seven people outside city hall in the border city of Nuevo Laredo.
Officials said the grenade went off around 11:15 a.m. on Friday in a truck parked outside the main municipal building in the city, which is across from Laredo, Texas, according to the Associated Press. All seven victims were hospitalized with non-life threatening injuries, and the front of the building was damaged, as were some nearby cars.
Police did not confirm whether or not the explosion was drug-related, but cartels in Mexico have been using explosive devices in vehicles more and more, reported Reuters. Most are relatively small in comparison to car bombs used in countries plagued by conflict, like Iraq.
Reuters also reported that soldiers, marines and police had sealed off the scene of the bombing in order to gather evidence to determine the type of explosive material used. Staff in the government hall evacuated the building immediately and emergency services were prepared for other explosions to occur.
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Nuevo Laredo and its Tamaulipas state is home to battles between the Zetas drug cartel and its former ally, the Gulf cartel, which has now allied itself with the Zetas' biggest rival, the Sinaloa gang, according to the AP. Sinaloa is led by Joaquin "El Chapo" Guzman.