CAIRO -- A car bomb destroyed about half of the empty French Embassy in Libya early Tuesday morning, in the most significant attack against a Western interest there since the killing last September of the American ambassador, J. Christopher Stevens.
Two French guards were injured in the attack, and one was in critical condition, said a French diplomat present at the scene.
The explosion was a new blow to the transitional Libyan government's hopes of establishing a better sense of public security after the ouster of Col. Muammar el-Qaddafi nearly two years ago. The blast was the largest in Tripoli since the end of the Western bombing campaign that helped force Colonel Qaddafi from power. It was the largest in a long string of smaller attacks on diplomatic missions, and it marks one of the first to occur in the capital.
As in previous attacks, no one claimed responsibility. But Libyans and international analysts have blamed Islamist militants for past attacks, and did so again in Tuesday's bombing.
Many Islamist militants in Libya have said that they are fighting a foreign attempt to remake their country as a Western-style liberal democracy instead of an Islamic state. They resent the Western powers for their military operations in Iraq and Afghanistan, to say nothing of the history of European colonialism in North Africa.
In particular, extremists have focused their anger, in posts on Facebook and other forums, against France for its intervention in neighboring Mali, a former French colony where French troops landed in January to help the central government roll back a hard-line Islamist takeover. The blast outside the embassy came just a day after the French parliament voted to extend the deployment of those troops.
Even during the uprising against Colonel Qaddafi, which was greatly aided by French military assistance, many Libyans suspected France and the other Western powers of intervening in order to seek oil or influence. And some Islamist militants further resent the West for its help because they believe the Western powers sought to "seize the revolution" in order to "recreate Libya in a Western image of secular democracy," said Professor George Joffe, a Libya scholar at Cambridge University.
The explosion outside Tuesday went off just after 7 a.m., before most employees had arrived at the building. Speaking on condition of anonymity, a Libyan official involved in investigating the crime scene said the blast had taken place when the Libyan guards who stand outside were changing their shift.
The force of the blast broke the windows and damaged the facades of more than two dozen buildings over an area as wide as 500 yards. Plumes of smoke billowed from the burning wreckage of a car, described by the official as a Renault, that was parked by the embassy walls. A burst water main flooded the street.
A resident living nearby, who spoke on condition of anonymity for fear of reprisals, compared the blast to the worst days of violence in Iraq. "I was knocked out of bed. I lived in Baghdad and I woke up to explosions as big as this one," she said.
In a statement, the Libyan government described the explosion as a "terrorist attack" and vowed "to cooperate with all parties to find the perpetrators and bring them to justice."
"The people and government categorically reject such acts," the statement said. "They do not reflect the respect and appreciation that the Libyan people hold for the French Republic and the French people," the statement added, specifically recalling French support for the revolution.
In Paris, President Franςois Hollande said the bombing was "aimed, by way of France, at all the countries of the international community engaged in the struggle against terrorism."
"France expects the Libyan authorities to shed the fullest light on this unacceptable act, so that the perpetrators are identified and brought to justice," Mr. Hollande added in a statement.
Laurent Fabius, the French foreign minister, arrived in Tripoli on Tuesday to meet with Libyan officials. The French and Libyan authorities would "make every effort to ensure that the circumstances of this odious act are exposed and its perpetrators quickly identified," Mr. Fabius said in an earlier statement from Paris.
Such an inquiry, however, may be difficult. The new Libyan government commands few disciplined police or military officers. Its forces often seemed outmatched by the freewheeling militias formed during and after the uprising against Colonel Qaddafi, and in fact it is sometimes hard to tell the difference between the autonomous militias and the loosely organized government fighters.
Attacks or bombings targeting Western diplomats have been more common around the eastern city of Benghazi, in a region known as a center of Islamist militancy. There was an attempted attack on the British envoy before the killing of Ambassador Stevens, and in January there was an attempted ambush there of the Italian consul.
Last month, Libyan security officials said they had arrested two men in the kidnapping near Benghazi of five British humanitarian activists, at least two of them women who had been sexually assaulted.
Most Western diplomats have pulled out of Benghazi and retreated to better-secured facilities in Tripoli, in the West. But the attack on the French Embassy may raise new questions about the possibility that militants may now try to strike other targets in the capital as well. It was the second attack in the capital following the hurling of a bomb at an empty United Nations compound in January.
"Until very recently everybody was pointing to the chaos and anarchy in Benghazi as the reason that an incident such as the attack on the U.S. consulate there could take place," said Claudia Gazzani, a Libya researcher for the International Crisis Group. "Now people are coming to grips with the fact that even in the capital, where you have the most presence of the state, that same kind of anarchy rules."
Reporting was contributed by Suliman Ali Zway from Benghazi, Libya, Osama Al-Fitori from Tripoli, Libya, Alan Cowell from London and Steven Erlanger from Paris.
This article originally appeared in The New York Times.