SEOUL (Reuters) - A Canadian pastor serving a life sentence in North Korea for subversion said he spends eight hours a day digging holes at a labor camp, while a naturalized American citizen said he is being held by the state for spying, CNN reported from Pyongyang.

South Korea-born Canadian pastor Hyeon Soo Lim stands during his trial at a North Korean court in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang December 16, 2015. REUTERS/KCNA

If the detention of the American, Kim Dong Chul, is confirmed, he would be the second Western citizen known to be currently held in North Korea. He is being held for spying for South Korea and has asked the South or the U.S. government to rescue him, CNN said, adding Kim is 60 and formerly of Fairfax, Virginia.

Hyeon Soo Lim, a South Korean-born Canadian who was the head pastor at one of Canada’s largest churches, has been held by the North since last February. Lim, who was 60 at the time of his arrest, was sentenced to hard labor for life in December for attempting to overthrow the North’s regime.

“I wasn’t originally a laborer, so the labor was hard at first,” Lim told CNN in Korean through an interpreter. “But now I’ve gotten used to it.”

The charges against Lim lacked specifics, but he said it may be related to his open criticism of the North’s three generations of leaders.

“I admit I’ve violated this government’s authority, system and order,” Lim said in the interview aired on Monday. Asked if his biggest crime was speaking badly of the North’s leaders, he said: “Yes, I think so.”

Lim’s family in Canada released a statement after the interview, urging the Canadian government to accelerate diplomatic discussions to secure his “speedy release.”

A spokesman for the Canadian foreign ministry said the government “is working towards a resolution in his case” and is concerned for his rights and well-being, but said no further information could be shared.

A church spokeswoman noted Lim’s changed appearance.

“We recognize that the difference in physical appearance is ‘standard’ for those sentenced in the DPRK but it’s never really standard (when) it’s a personal loved one. Having said this, we are hopeful because he himself was heard saying that he is at peace,” Lisa Pak, spokeswoman for the Light Korean Presbyterian Church in suburban Toronto, said in an email.

Lim was brought into a Pyongyang hotel for the interview, wearing a gray padded prison uniform bearing the number “036” on his chest, and with his hair cropped short. He said works eight hours a day, six days a week digging holes in an orchard at a labor camp where he has seen no other prisoners, CNN said.

Lim, who had lived in Canada since 1986, gets three meals and day and regular medical attention, CNN said. His church has said Lim had a “very serious health problem, very high blood pressure.”

Lim had visited the North more than 100 times since 1997 and helped set up an orphanage and nursing home, according to the church.

In a separate interview, Kim told CNN he spied on behalf of “South Korean conservative elements” and was arrested in October.

“I was tasked with taking photos of military secrets and scandalous scenes,” Kim said.

The U.S. embassy in Seoul said it was aware of the report but did not have further comment.

A U.S. State Department official declined to comment on the reports, saying that speaking publicly about specific cases of detained Americans can complicate efforts to get them released.

If his detention is confirmed, Kim would be the first American to be held by the North since it released three U.S. citizens in 2014.

He said he had moved to the Chinese city of Yanji near the border with North Korea and worked in the North Korean city of Rason in a trading business, when a number of South Koreans approached him

“They asked me to help destroy the (North’s) system and spread propaganda against the government,” he said. He is being held at a Pyongyang hotel and is in good health, CNN said.