A suicide bombing here that left the bomber and four policemen dead has raised serious doubts about peace efforts with separatist rebels.
The attack last week - at a police station next to the prime minister's official residence - was the first suicide bombing since the government and the Liberation Tigers of Tamil Eelam (LTTE) signed a cease-fire agreement in 2002.
The Tamil Tigers denied any involvement, claiming that the attack was an effort to discredit them and derail the peace process. But few believe this argument, pointing to the fact that the Tigers are the only organization in the country that has carried out suicide attacks.
The blast has shaken the confidence of Sri Lankans in the Norwegian-brokered peace process and brought into question the LTTE's commitment to find a political solution to the 20-year ethnic conflict that has claimed nearly 70,000 lives.
Some analysts say the government and the majority Sinhala community suspect that the LTTE, frustrated by lack of progress in peace talks, is trying to free itself of the cease-fire's constraints.
But the Tigers say that they are keen to hold talks and discuss a proposal of interim self-governance. They argue that the Sri Lankan armed forces are undermining the cease-fire agreement by providing shelter to renegade rebel leader Colonel Karuna, who broke from the Tigers in March.
"I don't think they are keen on breaking the cease-fire," says Pakiyasothy Saravanamuttu, executive director of the Center for Policy Alternatives here. "At the same time, they are also keen to be able to show that they will not be totally silent and unresponsive to what they consider to be provocations."
The female suicide bomber was initially caught while she was trying to meet a senior minister and leader of a Tamil political party, the Eelam People's Democratic Party, Douglas Devananda, in his office. Mr. Devananda, who has survived a dozen attempts on his life, has been encouraging the rebel Karuna to join politics.
"We cannot achieve anything without being in the political mainstream," says Devananda in an interview. "The armed struggle has only brought misery to Tamils."
The woman detonated her bomb as she was brought into the police station.
Shortly after Karuna rebelled against the LTTE, Tamil Tiger commandos swung down from the Tamil-dominated north and ousted him from his bastion in the district of Battlicaloa. The split in the LTTE has rattled the Tigers, who say Karuna has undermined their strength in the east and challenged their claim to be the sole representative of the Tamil community in Sri Lanka.
But even senior military officials say that an isolated suicide bombing does not indicate that the Tamil Tigers want to return to war. "They want to eliminate Karuna and his friends,'' says a senior official who requested anonymity. "The suicide bomber came for Devananda. If the Tigers want to break the cease-fire they will carry out simultaneous attacks like they did in 1994," when the Tigers broke a cease-fire after only 100 days with massive attacks around the country.
Still, Monday the Tigers accused the government of using Karuna's faction to weaken them and said that they are "ready to face ... war," according to a posting on a rebel website.
The European Union, which is the country's biggest donor bloc, has urged the government and the Tamil Tigers to return to the negotiating table. So far, no dates have been set for talks.
President Chandrika Kumaratunga says she wants to engage the LTTE in negotiations, but that discussion on interim self-governance should be linked to a search for a lasting political solution.
But the Tigers want their demand for self-governing authority be taken up first. And Karuna's defection and the suicide bombing have galvanized hard-liners in the majority Sinhala community who oppose efforts to restart peace talks.
Jathika Helu Urumaya, a political party of Buddhist monks with nine members in parliament, has called for a debate opposing interim self-governance.
Mr. Saravanamuttu says the bombing does not mean that the government cannot hold talks with the LTTE. "There is every reason to get to the table to avoid such situations," he says. "These only send a message that a peace process in limbo is a dangerous one."