Many Beslan victims gravely ill

Many victims were rushed to specialist hospitals in Moscow

Fifty victims of the Beslan school siege remain in a serious condition in Moscow hospitals, where 122 wounded are being treated, Russian officials say.

A senior health ministry official, Sergei Goncharov, said half of those most seriously hurt were children.

Thousands of schools across the EU held a minute's silence on Tuesday in honour of the Beslan victims.

Meanwhile, 20 Chechens who renovated schools in the Moscow area over the summer have been arrested.

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The Chechen conflict

Moscow regional security chief Nikolai Burkov, quoted by Russian media, said the group was detained near the capital's main Sheremetevo airport.

The militants who attacked the school in Beslan earlier this month, taking more than 1,200 hostages, are reported to have hidden arms and explosives on the premises while it was being renovated.

School term delayed

Officials have delayed the reopening of schools in Beslan - which was due to happen on Tuesday - as further security checks with sniffer dogs are carried out. They are now expected to reopen on Wednesday, Itar-Tass reports.

TRAGEDY IN NUMBERS 338 dead At least 84 bodies unidentified 727 hostages injured Russia's most wanted Agony goes on for relatives

Russian officials say the death toll from the three-day hostage crisis now stands at 338.

Apart from the 122 being treated in Moscow, 207 survivors are in hospital in North Ossetia, including 123 children. None of the latter are gravely ill, Mr Goncharov said.

The North Ossetian interior ministry says 84 bodies - including those of 52 children - remain unidentified.

Russia has blamed the mass hostage-taking in Beslan on Chechen rebels backed by foreign Muslim militants.

It has offered 300m roubles ($10m; £5.7m) for information leading to the arrest of Chechen rebel leaders Shamil Basayev and Aslan Maskhadov.