The human rights organisation, which has this week issued an 'Urgent Action' alert on the risk to ethnic minority and asylum-seeker groups in Russia, is concerned that - as in previous years - these groups could be the victims of racist attacks on or around 20 April.

Racially motivated attacks by skinhead and other gangs have been a growing concern in Russia in recent years, with 20 April becoming a particular focal point for an escalation of racially motivated harassment and violence.

According to the Russian Interior Ministry, there are around 20,000 skinheads in Russia and 2,500 in Moscow alone.

Amnesty International has recently documented a number of race attacks in Russia. For example, on 26 March 2003 two Cameroonian students were attacked by a 15-strong gang in the grounds of the Russian University of People's Friendship in south-west Moscow. Both students were injured and one needed hospital treatment.

In recent years the victims of racist attacks have included immigrants, refugees and asylum-seekers from Africa, Asia, Central Asia and the Caucasus, including ethnic Chechens.

Members of the Jewish community have also frequently been subjected to racial harassment and assault, and synagogues and Jewish community centres have been targeted.

Amnesty International UK Campaigns Director Stephen Bowen said: 'The horrible truth is that Hitler's birthday is a red letter day for violent racists in Russia, and people from ethnic minorities are especially vulnerable to abuse and attack at this time of year. 'The authorities in Russia have - at best - a mixed record when it comes to combating racial discrimination and violence and we are calling on them to prove their commitment to tolerance through heightened vigilance around the time of Hitler's birthday this year.'

Previous 20 April incidents have included:

• 2002: several foreign embassies in Moscow - including the USA's, Japan's and India's - received anonymous emails threatening to kill all foreigners in Russia. Embassies of seven former Soviet republics in the Caucasus and Central Asia reported that they had received numerous complaints about violent harassment on public transport and in outdoor markets.
• 2001: a Chechen man was stabbed to death in Moscow by a group of men; in another part of the city skinheads attacked ethnic Azeri merchants in a street market and destroyed their stalls and property.
• 1998: around the time of the anniversary a black United States Marine guarding the US embassy was assaulted by a group of unknown men as he walked through a Moscow park. He sustained serious injuries to his face.