The three southernmost provinces went into a tailspin yesterday morning as suspected insurgents launched a huge series of well coordinated bomb attacks, hitting at least 40 targets, mostly security positions and government installations, killing two people and injuring at least 25.

The attacks, launched between 8.30am and 9am, jolted the security and intelligence community amid growing criticism over their inability to curb the violence.

At least 10 police installations and outposts in the three Malay-speaking provinces were attacked and in one incident an M79 grenade launcher was used.

Beside the high level of coordination, the attacks also struck at the heart of towns and cities as police counted at least 10 bombs, mostly hidden in bathrooms, that went off inside the main buildings where provincial and district officials were working.

Bombs exploded inside the main buildings of four city halls, two provincial offices, two district police stations and two municipality offices.

In Pattani's Nong Chik district office, a bomb went off in the toilet a few metres from the central working area. The district chief was reported to have passed out from the commotion.

The latest episode of violence is unprecedented as previous bombings of government offices have mainly involved devices placed within a compound, not inside the main building. The bombs were detonated by clocks and cell phones.

Two public schools also received bomb threats but no explosions were reported.

Caretaker Prime Minister Thaksin Shinawatra was lost for words as to why the authorities were unable to prevent yesterday's attacks. Thaksin said intelligence indicated insurgents were planning a "major operation" but the government's preventive measures were "not good enough".

One of the bombs went off at a government office in Yala minutes before acting Deputy Prime Minister Chidchai Vanasatidya was to visit the area. Chidchai is in charge of overseeing security in Thailand's south. A 40-year-old man was detained shortly after the explosion in Yala city hall.

One man died in a blast at a teashop near Pattani's Khok Pho district office. It wounded 12 others. The shop is frequented by police and soldiers.

A second fatality in the province occurred when a local government worker's vehicle blew up while being inspected at Pattani City Hall. The worker was heading to his office when a security guard saw a suspicious object beneath the vehicle and yelled at him to jump out of the car. The driver escaped but moments later an explosion killed the guard and injured two others.

Many of the bombs were planted inside the bathrooms of provincial offices and police stations, injuring three police officers in Yala province and five marines in neighbouring Narathiwat, police said.

Yesterday's attacks came on the ninth anniversary of a conference that Thai intelligence said was held in Germany in 1997 and attended by about 10 exiled leaders of the Majlis Permesyuratan Rakyat Melayu Patani, or the Consultative Council of Patani Malays.

While the intelligence community gives importance to the date, June 15 is not widely accepted among the known separatist groups such as Patani United Liberation Organisation, Barisan Revolusi Nasional or Bersatu.