The family of Reverend Hyeon Soo Lim, a Korean Canadian pastor who is detained in North Korea, expressed urgent concern regarding his health and detainment following the recent death of American student Otto Warmbier.

“We are desperate to see our husband and father home, and we are pleading for an active escalation in diplomatic efforts,” the family said in a statement released on Wednesday.

Lim was sentenced to hard labor for life, and has been detained since January of 2015. Though he has had much exposure to the reclusive country and has been to North Korea more than 100 times on humanitarian endeavors, he was detained during his visit into the country in December of 2014 on accusations that he was attempting to overthrow the government.

Since Lim’s detainment, there have been reports of Canada’s contact with the North Korean government, and Lim himself also appeared in a CNN interview.

However, Warmbier’s death following his return from his detainment in North Korea, has ramped up a sense of urgency from the family.

“The family is very concerned at this point,” Lisa Pak, a spokeswoman for Lim’s family, was quoted as saying by Reuters. “They are hoping the Canadian government will turn (efforts) up a few notches in terms of active diplomacy and really start engaging.”

Pak added that the last time Lim’s family was able to receive any update on his situation was in February, when Lim was able to speak to them through a Swedish ambassador’s phone.

“We have not had an update on his whereabouts or his condition in several months,” she was quoted as saying by the Toronto Sun.

“Reverend Lim’s sentence is, in essence, a death sentence; and with each passing day, the family, the church, Canadians and people around the world fear for his life.”

Lim served as the senior pastor of Light Presbyterian Church in Toronto, and also has formed relationships with key Korean Christian leaders in the U.S. and South Korea. Multiple prayer gatherings on his behalf have taken place in Canada and the U.S. since his detainment.