"We have knocked on the doors of all the countries that could help us," Fouad Siniora told a news conference after the cabinet's weekly meeting.

"We are not facing an ordinary criminal...But we will gather all the tools, training and expertise we can obtain to live up to the challenge," he said.

The countries which have responded positively to Lebanon's plea were the United States, France, Russia, Egypt and Qatar, Siniora said. The government has also asked for help from six other states including Britain, Canada and China.

Twelve explosions have rocked Lebanon since the Feb. 14 assassination of former Prime Minister Rafik al-Hariri, which plunged the country into its worst political and security crisis since the end of the 1975-1990 civil war.

Many in Lebanon blame the killing and the ensuing attacks on Syria, the most dominant force in its smaller neighbour since the end of the war.

Damascus has denied involvement but the murder sparked mass protests in Beirut and forced Syria to bow to world pressure and end its 29-year military presence in Lebanon in April.

The ensuing blasts have piled pressure on Lebanon's government to tighten its grip on security ahead of the final U.N. report into Hariri's murder, expected next month.

Interior Minister Hassan al-Sabaa said on Monday that he was no way near identifying those responsible for the attacks. His remarks came one day after a car bomb badly wounded prominent news anchor May Chidiac.

Political bickering has stalled the appointment of security chiefs to replace three pro-Syrian generals who lost their jobs in the aftermath of Hariri's killing and have since been arrested on the recommendation of U.N. investigators.

They are now charged with murder in connection with planning the attack along with the current Republic Guard head, a close aide of pro-Syrian President Emile Lahoud.

Siniora said the government has made progress towards filling the three generals' positions but did not give further details. (Reuters)