YouTube yesterday pulled a video apparently showing the beheading of a Mexican drug cartel member by a rival gang, Associated Press reports.

The footage was the latest release in the online war of words between eastern Mexico's "Gulf Cartel" - with its private army "Los Zetas", led by Osiel Cardenas - and traffickers from western state of Sinaloa, headed by Joaquin 'El Chapo' Guzman.

The video - posted by "matazetaregio" - opened with the message "Do something for your country, kill a Zeta!" and continued to show "a man in his underwear tied to a chair with a 'Z' and the message 'Welcome, kill women and children. Continue Ostion' written on his chest".

The identity of Ostion is a mystery, AP notes, but the victim also had the name "Lazcano" inscribed on one leg - possibly a reference to the alleged head of the Zetas, Heriberto Lazcano.

The man was seen being "interrogated" about the 6 February deaths of "five police officers and two secretaries in the Pacific resort city of Acapulco". More than a dozen men assaulted two police stations and the authorities are investigating the possibility than some of the victims were connected to drug cartels and the killings were a "settling of scores" between gangs.

The video continued to show the man beaten into confessing he participated in the Acapulco killings, at which point he is strangled by "twisting a cord tied to metal rods until the pressure cuts through his neck".

The video ended with the message: "Lazcano you're next." A spokeswoman for Mexico's Attorney General's office told AP she had "no information on whether the video was being investigated by authorities". ®