BY JUAN O. TAMAYO

  CARACAS - Like a Wild West showdown, six opponents of President Hugo Chávez on Thursday met one of his military guards in the middle of a street blocked off by police, with cheering pro and anti-Chávez crowds at each corner, to deliver a statement demanding the leftist president resign.

  ''We have come to end communism in Venezuela,'' said retired Army Col. Hidalgo Valera, who led a march by some 4,000 Chávez opponents to the dramatic encounter five blocks from the whitewashed Miraflores presidential palace.

  ''They will not pass,'' a smaller pro-Chávez crowd chanted four blocks from Miraflores, separated from the opposition marchers by four thick lines of police and National Guard riot units.

  The protests ended peacefully, unlike one April 11 that ended with pro-Chávez gunmen firing on the opposition. Enraged military commanders immediately toppled
  Chávez, but loyalists returned him to power April 14.

  As the protesters marched Thursday, Chávez made a surprise visit to the shantytown of Las Malvinas, in south-eastern Caracas, warning supporters to be aware of
  another coup attempt.

  ''At any moment they can try to lash out at us like on April 11,'' he said according to The Associated Press.

  Thursday's march, called by a group of retired military officers to present a letter at Miraflores demanding Chávez's resignation, had fanned fears of a new confrontation because the officers had vowed to wear their old uniforms -- a military code violation that could have led to their arrests.

  In the end the officers decided to march in civilian clothes -- though Valera was arrested afterward by the secret police, the DISIP, on charges of wearing his uniform during a news conference Wednesday -- and agreed to stop the march five blocks short of Miraflores.

  ''The likelihood of another massacre is high,'' retired Navy officer José Angel Cano said as he waited for the arrival of the delegation from the presidential palace that would receive the march leaders' statement.

  Some 2,000 Chávez supporters blocked their way, chanting ''the streets belong to the people,'' and ''Down with Bush'' and holding up signs from the pro-Chávez Ernesto ''Che'' Guevara Revolutionary Front.

  Police guarding both sides turned up with empty pistol holders -- ''to avoid any possible incidents,'' Caracas Police Chief Henry Vivas said -- and carried only tear gas and shotguns loaded with plastic pellets.

  Valera refused to hand over the marcher's letter to an attorney from the presidency's Citizens Assistance Office and instead delivered it to National Guard Lt. Col. José Betelmi, assigned to the Miraflores honor guard.