They are accused of "undermining the defence of the country, of committing treason and of directly cooperating with the enemy", said the command of the Krusevac garrison.

In a signed statement read out on local TV, the army confirmed two protests had taken place on Monday and Tuesday in Krusevac.

In placing charges it said it was acting "in accordance with the law on the state of war", adding the protests had become destructive and taken advantage of parental feelings.

"The destructive demonstrations in Krusevac on 17 and 18 May were intended to break our defence capabilities," it said.

The protesters were said to be mainly wives and mothers of reservists called up to serve in the Yugoslav army in Kosovo.

A television station in Montenegro claimed several stones were thrown at the mayor of Krusevac, a member of the ruling Socialist Party.

Third protest reported

Opposition sources reported a similar protest in the nearby town of Aleksandovac.

There a crowd is reported to have attacked bodyguards of the town's mayor, who is also from the Socialist Party.

Many of the reports came the Montenegrin media and via the Democratic Party of Yugoslavia, which opposes the rule of President Milosevic.

It appears the demonstrations were provoked by the return of the bodies of seven reservists from Krusevac and three from Aleksandrovac.

The reports from the Montenegrin media said the mayor of Aleksandrovac was "literally lynched".

Most demos anti-Nato

But our correspondent in Belgrade says the severity of the violence was unclear and reports should be treated with caution until confirmed.

The Belgrade authorities maintain a firm grip on the news media and it is likely that news of anti-government protests would be suppressed.

Demonstrations against Nato are an almost daily occurrence across Yugoslavia.