BEIJING -- Chinese mainland police have repatriated more than 260 suspects wanted by Taiwan since the two sides formed a mutual assistance mechanism in crime fighting in 2009, a mainland official said on Wednesday.

Mainland police have also transferred six seriously ill prisoners to their Taiwan counterparts in the past four years, Yang Yi, spokesman for the State Council's Taiwan Affairs Office, told a press conference.

Taiwanese police had for their part repatriated four fugitives to the mainland, Yang said.

Police across the Strait have cooperated in busting a number of major telecom fraud gangs and seizing more than 4,100 suspects, according to the spokesman.

They jointly cracked many serious drug-trafficking cases, confiscating various drugs with a total weight of over 1,720 kg.

They have also investigated a series of economic crimes and cases concerning human-trafficking and illegal border-crossings under the Cross-Strait Agreement on Joint Crime Crackdown and Mutual Judicial Assistance.

In June of 2012, police from both sides captured 208 suspects implicated in a single bank card fraud case involving 1 billion yuan (160 million U.S. dollars.

Some 23,000 items of evidence have furthermore been delivered between the mainland and Taiwan since their crime-fighting mechanism came into place, said Yang.

He noted that the mainland has kept simplifying procedures for Taiwanese people to travel, work and live in the mainland, and will fast-track promoting E-entry permits for Taiwanese.