“Both the infected children are more than one-year-old and belong to the Mir Ali town of the tribal district,” according to the health ministry spokesperson.

Pakistan on May 23 started a nationwide polio vaccination programme, aimed at reaching as many as 43.3 million children under the age of five across the 156 districts of the country. The campaign will run for seven days in major cities and for five days in small cities.

“This is a moment of worry for us,” Health Minister Abdul Qadir Patel said in a statement. He urged the parents to get polio drops for their children under the age of five.

“Children are our future and we cannot let them become disabled. We have a firm resolve to end the crippling disease,” said Patel, who joined the federal cabinet on April 29.