ISLAMABAD — Continuing a militant campaign of violence against aid workers in Pakistan, gunmen on Tuesday shot dead seven Pakistani teachers and health workers, six of them women, police officials said.

There was no immediate claim of responsibility. But the shooting, in the Swabi district of the northwestern province of Khyber-Pakhtunkhwa, fit a pattern of attacks against charity and aid workers across the country in recent weeks that officials have attributed to the Pakistani Taliban. The militant offensive has brought a wave of international outrage, particularly because it has focused on vaccination and health workers in a country where polio and measles have made troubling gains.

The attack on Tuesday, near the village of Sher Afzal Banda, was conducted by two men on a motorcycle who followed a van taking the workers home and then opened fire on it with assault rifles, the police said. The victims worked for the private Pakistani aid group Support With Working Solution, which works in the health and education sectors.

“They opened fire and killed six females and one male,” Javed Akhtar, the group’s executive director, said in a telephone interview. “One child, aged 7 to 8 years, miraculously survived.”

The aid group was founded in 1991 and, in conjunction with other aid groups, has focused on Khyber-Pakhtunkhwa Province and on South Waziristan in the tribal region. Five of the dead were young women who worked as teachers at a primary-level school the charity ran in the area, Akhtar said. The other two were health workers.

While Akhtar said that his organization had received no prior warning or threat, he and other Pakistani officials said they believed that the attack was part of the broader Pakistani Taliban campaign against aid workers. Last month, at least nine Pakistani volunteers in an internationally supported polio vaccination drive were killed by militants across the country.

Pakistan is one of just three countries in the world in which polio remains endemic, and the country has also struggled with a resurgence of measles. Saghir Ahmed, the health minister for Sindh Province, fired five health department officials after six children were reported to have died of measles on Monday alone.

In the city of Karachi, at least four people were killed and more than 40 wounded Tuesday in a bombing that appeared politically motivated. The bomb, detonated by remote control, ripped through several buses returning from a political rally, the police said.