Chinese fishermen, returned from the DPRK, queue up to take a physical examination at a hospital in Dalian, Northeast China's Liaoning province, May 21, 2012. [Photo/Asianewsphoto]

All detained Chinese fishermen and their vessels arrived at Dalijia fishing harbor in Dalian without paying any "ransom", after the foreign ministry of the Democratic People's Republic of Korea confirmed they had been freed on May 20.

Zheng Xiujun (second left), a Chinese fisherman returned from the DPRK, talks with a reporter at a hospital in Dalian, Northeast China's Liaoning province, May 21, 2012. [Photo/ Asianewsphoto]

Fishermen received health checkups and were deemed in good condition.

Zhang Shouyi, 28, from Taihe county in Anhui province, was one of the 29 fisherman detained. He said he and seven other crewmembers were held in a small room of about three square meters.

He said they had trouble sleeping and getting enough food.

He also said their cell phones and wallets were taken away, and he still couldn't contact his family in Anhui because all the phone numbers were in the phone.

"I'm afraid they will worry about me, because they thought I was working in Shandong and don't know I'm here. So I plan to call them in a day or two."

It was reported that three fishing boats with 29 Chinese onboard were held in custody by a DPRK gunboat on May 8, and hijackers initially demanded payment of 400,000 yuan ($63,000) for each boat, then lowered their request to 300,000 yuan each.

After the incident, the Chinese government was in close communication with the DPRK to push for a proper resolution to the issue. Foreign Ministry spokesman Hong Lei said earlier that China demanded the DPRK ensure the safety and legitimate rights and interests of the Chinese fishermen

Counsellor Jiang Yaxian, with the Chinese embassy in Pyongyang, said Friday that the detained Chinese crews were in "sound health condition with sufficient food and healthcare," and that "some of the detained vessels and crews have already returned to China".