Syrian troops exchanged fire with Lebanese soldiers and armed groups in northeast Lebanon overnight and into Monday in a new round of clashes along the border.

There have been frictions along the mountainous frontier in the months since Islamist rebels toppled Syria’s Bashar al-Assad, an ally of Tehran and Iran-backed Lebanese armed group Hezbollah, and installed their own institutions and army, Reuters reported.

Late on Sunday, Syria’s defence ministry accused Hezbollah of crossing into Syrian territory and kidnapping and killing three members of Syria’s new army.

Hezbollah denied any involvement. A Lebanese security source told Reuters the three Syrian soldiers had crossed into Lebanese territory first and were killed by armed members of a tribe in northeastern Lebanon who feared their town was under attack.

In retaliation for their deaths, Syrian troops shelled Lebanese border towns overnight, according to the Syrian defence ministry and the Lebanese army. Residents of the town of Al-Qasr, less than one kilometre from the border, told Reuters they fled further inland to escape the bombardment.

Lebanese President Joseph Aoun said he ordered the army to respond to sources of fire from northern and eastern borders with Syria, according to a statement by his office. Aoun said the state would not allow clashes along the border to continue.

Lebanon’s army said in a statement on Monday that it had handed over the bodies of the three killed Syrians to Syrian authorities, and that it had responded to fire from Syrian territory and sent reinforcements to the border area.

Syria’s army sent a convoy of troops and several tanks to the frontier on Monday, according to a Reuters reporter along the border. Syrian troops fired into the air as they moved through towns on the way to the border.

“Large military reinforcements were brought in to reinforce positions along the Syrian-Lebanese border and prevent any breaches in the coming days,” said Maher Ziwani, the head of a Syrian army division deploying to the border.

Separatist militants drove a vehicle laden with explosives into a paramilitary convoy, killing at least five in southwestern Pakistan, officials said on Sunday, just days after the same group hijacked a train and held hostages for 36 hours.

The Baloch Liberation Army claimed responsibility for the attack in the district of Noshki in the restive province of Balochistan, Reuters reported.

Senior Superintendent of Police for Noskhi district Hashim Momand said more than 30 paramilitary force members were also wounded.

Pakistan’s Prime Minister Shehbaz Sharif in a statement condemned the attack, which came as Pakistan deals with a growing security crisis in its regions bordering Afghanistan.

The BLA on Tuesday took over the Jaffar Express in a remote mountain pass in Balochistan province, blowing up train tracks in an attack that killed 31 soldiers and civilians, the military said.

In Khyber Pakhtunkhwa province, which lies to the north of Balochistan and also shares a border with Afghanistan, the provincial chief minister Ali Amin Gandapur condemned a series of attacks on police across the province.

He did not provide casualty numbers, but the Tehreek-e-Taliban Pakistan (TTP) militant group said there had been 16 attacks in the past 24 hours.

Pakistan’s authorities have vowed to crack down on the growing insurgencies and said they are fuelled in part by militants finding safe haven in Afghanistan, a charge the ruling Islamic Emirate deny. Militant attacks often pick up in the warmer spring period as the cold winter months recede in mountainous border regions.

Cleric Mufti Munir Shakir, the founder of the outlawed Lashkar-i-Islam, succumbed to injuries he received from a blast in Peshawar on Saturday, DAWN reported.

A statement from the police spokesperson said the incident took place in the vicinity of Urmur Police Station and Mufti Shakir was injured on his left foot in the blast. It said the other three injured in the incident were Khushal, Abid and Syed Nabi.

The statement added that personnel from the police, bomb disposal unit and Counter-Terrorism Department were present at the scene and evidence was being collected.

In a video message, Mohammad Asim, a spokesman for the Lady Reading Hospital (LRH), said: “Mufti Shakir was brought to LRH in critical condition and succumbed to his injuries,” adding that the hospital was in the process of handing over the body to his heirs.

Special Assistant to the Khyber Pakhtunkhwa Chief Minister on Health Ehtesham Ali issued a statement on the matter, saying he was “deeply saddened” to hear of the development.

CM Ali Amin Gandapur condemned the blast and sought a report from the police authorities on the incident. The chief minister directed authorities to carry out the “necessary steps” to arrest the suspects behind the blast and expressed his best wishes for the speedy recovery of the injured.

CM Gandapur also directed the hospital administration to provide the best medical assistance available to the injured.

Lashkar-i-Islam — a Bara-based militant organization in Khyber tribal region led by Mangal Bagh — was banned in 2008.

A local cleric in Bara, Mufti Shakir formed the Lashkar-i-Islam in December 2004 after Sipah and Malikdinkhel tribesmen announced their full allegiance to him. However, the cleric was expelled from Bar Qambarkhel area after only six months owing to his extremist views and differences with Haji Namdar, another militant commander of the area.

Both Mufti Shakir and Pir Saifur Rehman were forced to leave Bara after a jirga of local elders gave a consensus verdict following bloody clashes between the supporters of the two in early 2005. Mangal Bagh, a bus driver-turned-militant was elevated to the position of amir (chief) of Lashkar-i-Islam in May 2005.

Pakistani security forces demolished the house of Haji Rabat and destroyed the FM radio station set up in a mosque after they started the first military operation against Lashkar-i-Islam in mid-2005.