BEIJING — Chinese police provided about 746,000 unregistered citizens with household registration permits, a crucial document entitling them to social welfare, in the first five months of this year, according to the Ministry of Public Security.

In China, various social benefits such as medical insurance and access to basic education are based on permits known as “hukou” and are supposed to be in line with long-term places of work and residence.

The move to register unregistered citizens, which are estimated at 13 million, or 1 percent of the entire population, was announced in December. Between January and May, more than 1.09 million unregistered people were confirmed, the ministry said in a statement issued on June 8.

They include orphans and second children born illegally under the one-child policy, the homeless and those who have yet to apply for one or who have simply lost theirs. Parents who violated family planning policy often refrained from getting hukou for their children in order to avoid fines.

The ministry also revealed that police across the country have confiscated three million duplicated hukou and more than 1.7 million IDs that have duplicated numbers.

The ministry said last year that some of the duplications were honest mistakes from manual errors or separated police management systems in the past, but others were the result of police officers illegally using professional privilege to seek benefits for their connections.