A total of 12 people were killed by insurgents in Pattani, Narathiwat, Yala and southern Songkhla in a series of attacks stretching over Monday and Tuesday.
Police said two rubber tappers were ambushed and killed on a local road at a rubber plantation in Pattani's Khok Pho district early Tuesday morning.
They were identified as Phon Phetsorn, 66, and his wife Nid, 68, residents of Ban Kluay in tambon Na Pradu of Khok Pho district.
Witnesses told police the couple were travelling to work on a motorcycle when gunmen hiding in the roadside forest fired on them with an AK47 assault rifle and 11mm handgun. The assailants then fled.
The victims were hit several times in the head and torso and died on the spot.
On Monday night, another couple were shot dead in Khok Pho.
The victims were identified as Supachai Chuaysaen, 27, and his wife Sirikwan Saengtong, 24.
Police said the Buddhist couple were travelling on a motorcycle in front of the Office of the Rubber Replanting Aid Fund about 8pm when gunmen opened fire at them and then fled.
Police blamed separatist militants for both attacks.
Suspected insurgents kill three defence volunteers before making off with their firearms in Pattani on Oct 8, 2012. (Post Photo)
In Pattani's Yaring district on Monday afternoon, three defence volunteers were shot dead and the killers made off with their firearms.
Surasak Saksongmuang, 27, and his father Nam Saksongmuang, 57, were found dead on the Yaring-Ban Muang Wan road next to a pickup truck.
Somsak Khunchum, 42, was found dead inside. Their bodies and the vehicle were riddled with bullets.
The trio were on their way back from a security meeting at Yarang district office when they spotted someone on a motorcycle they knew and stopped for a chat near Ban Yai in tambon Ratapanyang.
A pickup truck then drove past and two men on the back opened fire at the defence volunteers' vehicle. The motorcycle sped away.
The attackers searched the pickup and took with them an AKA rifle, an M-16 rifle and two pistols before fleeing.
Police found more than 100 spent cartridge shells scattered on the road.
On the same day a pair of Muslim men were also killed in a drive-by shooting in neighbouring Yala province, police said. Their names were not released.
Two vegetable vendors were also shot dead in Songkhla province, which had been relatively untouched by the violence until a number of attacks this year, including a series of car bombs in April that left 15 people dead.
In Narathiwat's Cho Airong district, a village health volunteer was killed in a drive-by shooting on Tuesday morning.
Pol Lt Kaweepat Kraiperm, a duty officer at Cho Airong police station, said the attack occurred on the Sungai Padi-Cho Airong road at Ban Sormong of Cho Airong about 6am.
Police found five spent cartridge shells from a 9mm handgun at the scene and were told that an injured woman had been taken to Cho Airong hospital.
The victim was identified as Suena Seng, 44, a health volunteer at Ban Aye Payae. She was hit by three bullets - in the head, right shoulder and torso.
The victim's husband, Sama-air Seng, 49, told police that he, his wife and another woman were travelling along the road to work at their rubber plantation when a gunman riding pillion on another motorcycle fired on Suena. The attackers then fled.
Suena and the woman passenger fell from the motorcycle but Mr Sama-air escped unhurt. The woman passenger was also unhurt in the attack. The sattackers fled.
Mr Sama-air said he asked the driver of a passing pickup truck to take his wife to Cho Airong hospital, where she was later pronounced dead.
Separatist insurgents were blamed for the murder.
Since the resurgence of the insurgency in January 2004, there have been about 11,000 violent incidents instigated by secessionists in the Muslim-dominant southernmost provinces of Yala, Pattani and Narathiwat, with almost 5,000 people killed and nearly 8,000 injured.