Quetta: At least three people were killed and six were injured in a bomb attack, targeting two vehicles in Pakistan's Mastung district on Friday, local media reported.

The official said that the unknown armed men targeted the vehicles, which were carrying people who were travelling back after burying a man killed by unknown armed men in the Dasht area, Dawn reported.

Dawn citing sources reported that an improvised explosive device (IED) planted at a roadside went off when the vehicles were passing through the area.

In that attack, three people died on the spot. The bodies and the injured were taken to Mastung district hospital.

"An IED was planted at the roadside to target the convoy of the tribal elder and the people travelling with him," a senior Levies official said, adding that the IED was detonated by remote control.

"We have received three bodies and six injured," an official at the Mastung district hospital said, adding that the condition of three of the injured is serious.

This is not the first time that an attack took place in Quetta.

Earlier, four people were injured after unidentified motorcyclists hurled a hand grenade on the Sariab Road of Pakistan's Quetta at a security check post on Saturday night, Dawn reported.

The police official said that four civilians, who were walking on the side of the road when the attack took place, were injured and two of them were taken to the hospital, reported Dawn.

"We have received four injured in the trauma centre," said Dr Wasim Baig, a hospital doctor.

Security forces cordoned off the area and launched a search operation and took some suspects for interrogation.

No organisation has claimed responsibility for the attack, reported Dawn.

Earlier, on October 7, three people were injured after unidentified attackers hurled a hand grenade in the Hayatabad suburb of Pakistan.

The incident took place in Phase-1, Hayatabad where unidentified attackers threw a grenade into a house and the subsequent explosion wounded three people who were later rushed to a nearby hospital, Dawn reported. Hayatabad, where the explosion took place is a suburb on the western outskirts of Peshawar, the capital of the Khyber Pakhtunkhwa province of Pakistan.

According to Dawn, a house in the same township had been attacked with a grenade a few days ago, injuring one person.

Meanwhile, one person was injured in a cylinder blast in the Industrial Estate of Hayatabad Friday evening.

The highest number of terror incidents in Pakistan this year was recorded in September, said an Islamabad-based think tank, as it pointed to the resumption of attacks by the outlawed Tehrik-i-Taliban Pakistan (TTP).

The number of terror attacks increased in September compared to August this year, the Dawn newspaper reported citing the Pakistan Institute for Conflict and Security Studies (PICSS).

September witnessed 42 militant attacks with an increase of 35 per cent compared to August. The Pakistani think tank also observed an increase of 106 per cent in violence in erstwhile FATA and Khyber Pakhtunkhwa (KP).

In August this year, the think tank said the militants carried out 31 attacks across Pakistan, where 37 people were killed and 55 others injured.