Quetta, Pakistan. Gunmen in southwestern Pakistan killed at least 31 people in two separate attacks on Monday, with reports of other shootings and unrest across the same province, police and officials said.

Twenty-three people were fatally shot after being identified and taken from buses, vehicles and trucks in Musakhail, a district in Baluchistan province, senior police official Ayub Achakzai said. The attackers burned at least 10 vehicles before fleeing.

In a separate attack, gunmen killed at least nine people, including four police officers and five passersby, in Qalat district also in Baluchistan, authorities said.

Insurgents blew up a railway track in Bolan, attacked a police station in Mastung, and attacked and burned vehicles in Gwadar, all districts in Baluchistan. No casualties were reported in those attacks.

Baluchistan has been the scene of a long-running insurgency in Pakistan, with an array of separatist groups staging attacks, mainly on security forces. The separatists have been demanding independence from the central government in Islamabad. Although Pakistani authorities say they have quelled the insurgency, violence in Baluchistan has persisted.

The attack in Musakhail came hours after the outlawed Baluch Liberation Army separatist group warned people to stay away from highways as they launched attacks on security forces in various parts of the province. But there there was no immediate claim of responsibility for the latest killings.

Separatists often ask people for their ID cards, and then abduct or kill those who are from outside the province. Many recent victims have come from neighboring Punjab province.

Uzma Bukhari, a spokesperson for the Punjab provincial government, denounced the latest killings on Monday, saying the “attacks are a matter of grave concern” and urging the Baluchistan provincial government to “step up efforts to eliminate BLA terrorists.”

Authorities in Baluchistan said they responded to the latest attacks on Monday and that they would provide details on their operations later in the day. Local media said at least 12 insurgents were killed by security forces in various parts of the province in the past 24 hours.

Pakistani President Asif Ali Zardari and Interior Minister Mohsin Naqvi in separate statements called the attack in Musakhail “barbaric” and vowed that those who were behind it would not escape justice.

Later, Naqvi also condemned the killings in Qalat

In May, gunmen fatally shot seven barbers in Gwadar, a port city in Baluchistan.

In April, separatists killed nine people after abducting them from a bus on a highway in Baluchistan, and the attackers also killed two people and wounded six in another car they forced to stop. BLA claimed responsibility for those attacks at the time.

Syed Muhammad Ali, an Islamabad-based security analyst, said the latest killings of non-Baluch people are an attempt by separatists to harm the province economically.

Ali told The Associated Press that most such attacks are carried out with the aim to economically weaken Baluchistan, noting that “the weakening of Baluchistan means the weakening of Pakistan.”

He said insurgent attacks could hamper development work being done in the province.

Separatists in Baluchistan have often killed workers and others from the country's eastern Punjab region as part of a campaign to force them to leave the province, which for years has experienced a low-level insurgency.

Most such previous killings have been blamed on the outlawed group and others demanding independence from the central government in Islamabad. Islamic militants also have a presence in the province.