A gas attack on a Portuguese discotheque has left seven dead and some 60 injured. The assault occurred in the early hours of Sunday morning, April 16, when two canisters containing a toxic gas were thrown into the crowed “Luanda” discotheque in Lisbon. The club was popular with Angolan and other African immigrants. The dead included six people of African origin and a Spanish biology student from Madrid.

Doctor Rita Peres of the emergency service at San Francisco Javier Hospital said that most of the injured had suffered multiple trauma and respiratory problems. Police are studying security camera footage, which may give a clue to the identity of the attackers.

Eyewitnesses say the gas was possibly either pepper spray or tear gas, but officials have still to confirm its contents. Most of the deaths and injuries seemed to have occurred in the panic following the release of the gas. The club's lights had been tampered with by the assailants and many were crushed in the rush for the exits. Barriers and chains used to control crowds at the club's entrance may have hindered the escape, causing several of those killed to fall over and be crushed. In the confusion, it took more than 15 minutes to clear the main entrance.

The attack is the worst to have occurred in Lisbon, although it is the seventh or eighth incident involving gas being let off in Portuguese discos in the last six months.

Police claim that the attack is part of a feud between rival African groups for control of the club scene, and dismissed any possible racist motives. This was echoed by the Portuguese Prime Minister Antonio Guterres, who described it as a result of a “conflict of interests” between Angolans and immigrants from Cape Verde.

However, a member of the security team at the Luanda discotheque said that although there had been some trouble between the two groups in the past, this had largely involved arguments over women. He said the Angolans and Cape Verdeans were involved in “completely different businesses”; the Angolans were active in newer more modern discos that played Brazilian and Cuban music, whereas the Cape Verdeans were dominant in longer-standing premises that specialised in traditional music and dance.

The tragedy in Lisbon came exactly on the third anniversary of an arson attack on the Meia Culpa disco in Amarante, which left 13 dead. In the court case that followed, responsibility for ordering the attack was placed on Jose Queiros, the owner of a rival club.

Although discounted by the police, racism is certainly a possible motive for the attack at the Luanda discotheque.

One of the country's main newspapers, Diário de Notícias, published a report last week on “silent racism” in Portugal. The study was conducted in the university city of Coimbra, and looked in particular at the difficulties African students had in finding accommodation. According to students interviewed by the newspaper, many landlords do not even try to hide their racist sentiments and often openly say, “we don't rent to blacks”. Not infrequently, when African students do manage to secure accommodation, the rent they have to pay is much higher than the going rate.

Relations between Portugal and its former colony Angola worsened recently in a series of tit-for-tat expulsions. Twenty-seven Portuguese nationals were barred entry to Angola, following their arrival at Luanda International Airport. The Angolan authorities said that although they all possessed holiday visas they did not have work permits.

In the days that followed, 12 Angolans arriving in Portugal were sent back on the next flight, accused of having false passports. Recent figures that have come to light show that Portugal has deported an average of 19 Angolans a month since the beginning of the year.

Manuel Diogo, assistant secretary of state for Internal Administration, said the stricter immigration controls represented “greater rigour” on the part of Portugal in direct response to the actions of Angola.

The opposition Social Democratic Party leader Durao Barroso dubbed the government's actions “racist and xenophobic”. He said by retaliating in this way “the government has given in to demagogic populist pressures”.