"May God punish them for the crime they have committed against these youngsters, and their country," he said, weeping.
Interior Minister Yazid Zerhouni, who went to the scene surrounded by heavy security, called the bombing "an act against Algerians".
"These terrorist gangs are seeking through attacks against civilians to loosen the net closing around them as the security forces drive them to the wall," he was quoted as saying by the official APS news agency.
The Algerian government has long said that Islamist insurgents are desperately seeking to raise their profile as they are isolated by security forces.
The French EU presidency and Spain condemned the bombing, while Italian Prime Minister Silvio Berlusconi expressed his support for Algeria's leadership.
The attack came as Algerian newspapers reported that Islamist militants had ambushed eight policemen, three soldiers and a civilian near Skikda in eastern Algeria on Sunday.
ATTACKS IN ALGERIA 2007-2008
10 August 2008: Eight killed by suicide bombing outside police station in Zemmouri
8 June 2008: French engineer and driver killed east of Algiers
5 June 2008: Roadside bomb kills six soldiers east of Algiers
January 2008: Suicide bombing kills four policemen in Naciria
December 2007: Twin car bombs kill at least 37 including 10 UN staff in Algiers
8 September 2007: 32 die in bombing in Dellys
6 September 2007: 22 die in bombing in Batna
July 2007: Suicide bomber targets barracks near Bouira, killing nine
April 2007: 33 killed in attacks on government offices and a police station
Algeria has been struggling to emerge from a long civil conflict that started in 1992 when the army intervened to prevent a hardline Islamist party winning parliamentary elections.
Violence has been much reduced compared with the levels of the 1990s, but there has been a surge in high profile attacks - including suicide bombings - since late 2006.
In September 2006 the last significant insurgent group to survive the conflict, the Salafist Group for Call and Conflict (GSPC), confirmed an alliance with al-Qaeda.
Shortly afterwards it changed its name to al-Qaeda in the Islamic Maghreb.
Algeria is a major exporter of oil and gas.
In the most recent reported bomb attack, a suicide bomber at a beach resort killed eight people on 10 August.
In December two consecutive bombings in Algiers - including one at the UN's offices - killed at least 37 people.
Those attacks were claimed by al-Qaeda in the Islamic Maghreb.
No immediate claim of responsibility for Tuesday's bombing was reported.
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