Police voted to strike tonight for the second time in a week, casting a question mark over Mardi Gras.

After the overwhelming voice vote, Mayor Ernest A. Morial called off all Mardi Gras parades through Monday. Outside New Orleans, processions will go on as scheduled, starting today. Mardi Gras is Feb. 27.

The strike vote by the Teamster-affiliated Police Association of Louisiana came six days after the union agreed to return to work from a 42-hour walkout. During the hiatus, city and police association representatives were to negotiate such matters as pay and benefits, but those sessions broke off less than an hour before the union met tonight.

The walkout continued despite a temporary restraining order commanding the police to return to work.

New Orleans parades were called off despite the presence of hundreds of National Guardsmen and state police who had been summoned to maintain order. As the police voted to strike, the guardsmen and state policemen were given authority to make arrests and load their weapons with live ammunition.

However, they cannot fill the police role at parades because they are not equipped to cope with the "unique" conditions in a Mardi Gras crowd, said Maj. Gen. O.J. Daigle Jr., the state adjutant general.

Mardi Gras is worth about $250 million each year to New Orleans, and there is no way to estimate how much the strikes will cost the city, said Norman Kerth, president of the Chamber of Commerce.

Negotiations broke off tonight when city representatives refused to accept two union demands:

Inclusion of ranking officers in the proposed contract.

Continuation of bargaining still unsettled at that time to binding arbitration.

Emerging from the union meeting tonight, some members wore T-shirts saying, "Take this job and shove it."

About one million revelers participate in a typical year's celebration. In more than a century, Mardi Gras has been canceled only seven times -- twice for epidemics, five times for war.

In a reference to Teamster negotiator Joe Valenti from Detroit, the mayor said, "Mardi Gras this year might be killed by the actions of outsiders... without any real understanding of our city, our citizens or our system of government."