Four civilians were also wounded in the attacks, the military said.
MILF rebels blocked a portion of the Cotabato-General Santos Highway in Talayan town in Maguindanao as they fired at two delivery trucks, wounding the drivers and crew, and then used the commandeered vehicles as roadblocks.
The gunmen then boarded a Mitsubishi L-300 van that ran into the roadblock and shot dead eight male passengers after separating them from the women. The passengers were also robbed, said military spokesman Maj. Julieto Ando.
In another incident, MILF rebels entered the town of Midsayap in North Cotabato, and fired at the houses with automatic rifles, killing one resident, Ando said.
Rommel Gamiao, a wounded survivor of the highway execution, said he managed to survive by playing possum after he was shot by the rebels in the body and legs.
"It was fortunate that two other victims fell over me, I pretended I was dead. I noticed that the rebels finished them off with automatic weapons," Gamiao told The STAR.
Another passenger identified as Teodulo Sumilhig was found unconscious 16 kilometers away from the scene, having apparently passed out after running for his life.
Gamiao said he is certain that the eight other commuters died instantly. "All of them were no longer moving. I could not feel them breathe. Their bodies were all drenched in blood," he said.
Ando said they are still verifying the identities of the eight slain passengers. "We can’t release their identities until we have notified their respective families of their sad predicament," he said.
Ando said the rebels initially massed up in a roadside village shortly after midnight Monday and flagged down several vehicles.
Two of the vehicles the rebels managed to stop were light trucks loaded with fish from General Santos City.
Even as the rebels robbed the passengers and unloaded the fish cargo from the trucks, another group of rebels harassed an Army detachment in Barangay Bagan while simultaneously toppling three wooden electrical posts along the highway.
Local officials said 13 MILF rebels were killed after soldiers broke through the road barricade. Three rocket grenade launchers and four M-16 rifles were recovered from the slain rebels.
Armed Forces Southern Command (Southcom) spokesman Lt. Col. Daniel Lucero said reports reaching his office also indicated nine civilians were taken by the rebels.
"We are still trying to get the confirmed figure and determine their fate," Lucero said.
MILF spokesman Eid Kabalu said he was looking into the incidents but stressed the group did not attack civilians.
Kabalu said four soldiers were killed and eight wounded in the clash on the highway. He said he heard there were MILF casualties as well but would give no details.
Kabalu said renewed fighting with government troops and civilian casualties could be prevented with the presence of foreign peacekeepers from the United Nations (UN) in Mindanao.
Hesaid Muslim groups want foreign peacekeepers because a local committee of government and rebels tasked in safeguarding the truce has failed to stop violations and fighting.
"It’s toothless," he said of the committee. He cited the frequent clashes in the south, including ongoing fighting in southern Maguindanao and North Cotabato provinces that has displaced more than 40,000 people and left hundreds dead.
Likewise, observers from Muslim nations would have no peacekeeping function, Kabalu said.
Chief government negotiator Jesus Dureza said the government and guerrillas have already agreed to invite representatives of the Organization of the Islamic Conference (OIC) to monitor the ceasefire in Mindanao.
He said it would be best to implement this agreement before moving on to the other proposals.
But the presence of an international peacekeeping force might project the image that the country is engulfed in war, Dureza stressed.
An international peacekeeping force, preferably under the UN, "could really restrain both sides from firing at each other," said Abhoud Syed Lingga, chairman of a large Muslim group, the Bangsamoro People’s Consultative Assembly.
"Time and again we thought the ceasefire could hold back the firing only to find ourselves in the middle of this violence again," Lingga said.
Lingga said his group has relayed its proposal to the MILF and will inform the government later this week.
Sporadic gunbattles have erupted since the military overran Buliok complex, a main stronghold of the rebels in Pikit, North Cotabato last month.
The MILF said the offensive was a violation of a ceasefire agreement and cut off communication with government representatives.
The government accused the guerrillas of harboring the notorious kidnap gang Pentagon, which is on a US list of foreign terrorist organizations.
President Arroyo has sought the mediation of the Malaysian government to revive talks with the rebels, which were suspended in 2001. Kuala Lumpur hosted the previous talks.
Administration Sen. Robert Barbers, for his part, deplored the absence of a representative from Mindanao in the Cabinet oversight committee tasked to formulate plans for the resumption of peace negotiations with the MILF.
Barbers, who is from Surigao del Norte, said there was a need to review the composition of the Malacañang panel that will try to restart talks with Muslim separatist rebels.
"Malacañang seems to be tasking a lot of people but none of them are from Mindanao," Barbers said.
Barbers said the government should tap the services of Muslim and Christian religious leaders in Central Mindanao in seeking the resumption of peace negotiations with the MILF.
The Cabinet Oversight Committee on Internal Security (COCIS) was assigned by Mrs. Arroyo to draw up a peace formula to encourage the MILF to resume talks with the government.
Barbers also said Muslim and Christian religious leaders should be included in the ceasefire monitoring committee to prevent another escalation of violence due to a "misunderstanding" over tactical peace agreements.
Meanwhile, acting Southcom chief Maj. Gen. Generoso Senga said the ongoing military offensives against MILF rebels would not be affected by the impending war by the US against Iraq.
"Our concern here is more local. So we would not be affected. However, to a certain extent, we shall be also watching the movements of those we consider to take advantage of the situation and claim they would be acting in sympathy to what is happening in Iraq," Senga said.
He said that so far, no order for the deployment of Filipino troops for operations against Iraq has been ordered.
"So, our forces would remain intact and we will pursue what we have set to do," he said. – With Roel Pareño, Sammy Santos, Edith Regalado, Mike Frialde, AFP