The latest incidents occurred as Thai authorities prepared a state of emergency for insurgency-hit areas.
On Monday, suspected separatists in Narathiwat set off a bomb hidden on a bridge while a truck carrying soldiers and police passed by. Five soldiers and two policemen were hurt.
In other attacks on Monday, a man on a motorcycle fatally shot a teacher in Pattani and a rubber plantation worker was slashed to death.
A soldier was shot dead while on patrol on Sunday night in Narathiwat.
The new emergency decree was issued after insurgents attacked the Yala provincial capital on Thursday, destroying electrical transformers to black out the city, setting off firebombs and firing automatic weapons at security forces before escaping.
King Bhumibol Adulyadej signed the measure into law on Sunday.
Critics complain that the decree is unconstitutional and dictatorial.
Thai security officials recommended that the new state of emergency be imposed on the provinces of Yala, Pattani and Narithiwat - where virtually all the attacks in the 18-month-old insurgency have taken place - and parts of nearby Songkla province, Cabinet Secretary Bowornsak Uwanno said.
Thaksin says the decree,
criticised as draconian, is needed
The cabinet was expected to approve the recommendation and put the emergency into effect on Tuesday, he added.
The military already has been in the southern provinces in force since early last year.
The new decree expands the government's authority to impose curfews, ban public gatherings, censor news and close publications, limit travel, detain suspects without charge, confiscate property and tap telephones.
Prime Minister Thaksin Shinawatra says the measure is necessary to curb violence in the south, where about 900 people have died in hundreds of drive-by shootings and scores of bombings since Islamic separatists reignited a decades-old but dormant insurgency in January of last year.
Thaksin's critics say his hardline military response has worsened the conflict.
Nida Waba, a Muslim community leader in Pattani, said there will be no improvement in the south as long as Thaksin remains in office.
"Thaksin is not a troubleshooter - he is the one who is creating the problem in southern Thailand"
Muslim community leader
"Thaksin is not a troubleshooter - he is the one who is creating the problem in southern Thailand," he said .
Den Tohmeena, a southern senator whose father and brother were accused of being Muslim separatists in the 1970s, said the new law will make little difference to people in the south because they already feel under the thumb of what they consider a corrupt government.
"The local people are used to abuse of power by government officials and security personnel, so whatever decree or law is imposed will make no difference to them," Den said.