Islamabad, Pakistan (CNN) – A long-time Red Cross staffer has been killed by his kidnappers in Pakistan, the International Committee of the Red Cross and British government said Sunday.

Khalil Rasjed Dale, 60, was seized in Pakistan’s volatile southwestern province of Balochistan in January.

His body was discovered Sunday, and he appears to have been killed recently, ICRC spokesman Sean Maguire said.

Maguire acknowledged Pakistani press reports that Dale had been beheaded but declined to go into details about how he was killed, saying only: “It was a brutal murder that has left us appalled.”

The ICRC has identified Dale’s body and will be able to bring it home to Britain, Maguire said.

“We were in touch with the abductors a number of times during Khalil’s captivity,” he said. “We have called upon the Pakistani authorities to conduct a full and immediate investigation into the murder.”

“We are not going to talk about who may or may not be responsible for the killing,” he added.

The head of the ICRC, Yves Daccord, condemned Dale’s killing as a “barbaric act,” and said staff members of the international agency were “devastated.”

British Foreign Secretary William Hague said the killing was “a senseless and cruel act, targeting someone whose role was to help the people of Pakistan, and causing immeasurable pain to those who knew Mr. Dale.”

British Prime Minister David Cameron said he was “deeply saddened” by reports of Dale’s death, noting that he died while “providing humanitarian support to others.”

“This was a shocking and merciless act, carried out by people with no respect for human life and the rule of law,” Cameron said. “Khalil Dale has dedicated many years of his life to helping some of the most vulnerable people in the world and my thoughts today are with his friends and family.”