Oscar De La Hoya and Fernando Vargas grappled with each other at a news conference to formally announce their super welterweight title fight.

As the pair came together at a downtown hotel, they shoved each other, and Vargas grabbed De La Hoya's throat before they were separated.

Angry words were then exchanged throughout the rest of the conference.

Promoter Bob Arum said security was heavier than for any other boxing news conference he has been involved in.

A police officer stood at each end of the stage and several plainclothes security guards, employed by the hotel, were stationed nearby.

Mutual dislike

The fight will take place on 4 May at the Mandalay Bay Casino in Las Vegas for the WBC and WBA super welterweight championships.

De La Hoya, from east Los Angeles, will earn $14m plus a percentage of the pay-per-view sales, while Vargas, from Oxnard, California, will get $6m plus a percentage of the pay-per-view profits, Arum said.

The 28-year-old De La Hoya, the WBC super welterweight champion, has a 34-2 record with 27 knockouts while Vargas, 24, the WBA's 154-pound title-holder, is 22-1 with 20 knockouts.

De La Hoya and Vargas have made clear for years their dislike for each other, and Vargas told KEYT television in Santa Barbara earlier this week he has "no respect whatsoever" for De La Hoya.

"Fernando's looking forward to this fight, it's the fight of his dreams, the fight of his life," Vargas' manager, Rolando Arellano, said on Tuesday.