9 Arrested over wave of violence in northeastern Mexico

These latest detainees are associates of four other suspects captured on Wednesday, including the purported head of the crime gang, according to the Tamaulipas Coordination Group, or GCT, which comprises federal and state security forces.

Alleged members of the same unidentified gang responded to the four arrests by mounting roadblocks, burning vehicles and carrying out armed attacks against federal and state forces, actions that left one police dead and two suspected members of the gang wounded.

The nine arrests on Thursday were made at the Flores Magon ejido, a peasant community in Tamaulipas, when the suspects tried to flee after detecting the marines's presence.

Those federal forces seized 24 rifles, five handguns, a Claymore mine with an M57 firing device, two grenade launchers, five grenades, 58 ammunition clips, and rounds of ammunition of different calibers.

"Authorities from the three levels of government have the situation in the municipalities of Altamira, Madero and Tampico (in the southeastern tip of Tamaulipas) under control. Commercial establishments and schools are once again operating normally," the GCT said.

Tamaulipas, which borders Texas, has been for years a battleground between the Gulf and Los Zetas drug cartels and is regularly among the Mexican states with the highest numbers of homicides.

President Enrique Peña Nieto sent additional Federal Police and military personnel to Tamaulipas last May and ordered a thorough vetting of the state and municipal police forces to root out corrupt officers.