Updated

The four senators from New York and New Jersey, already seeking an investigation into the Lockerbie bomber's release from prison last year, kept the pressure up Wednesday by calling on BP to suspend its oil drilling plans in Libya until it can be determined whether the oil giant played any role in his release in exchange for a contract.

Abdelbaset al-Megrahi's release last year from a Scottish prison on "compassionate" grounds after doctors estimated he had only three months to live has come under suspicion following a report that the cancer-stricken Libyan could live another decade.

At a news conference Wednesday, Sens. Bob Menendez of New Jersey and Charles Schumer of New York, both Democrats, called any profits BP might make from drilling off the coast of Libya "blood money."

The four senators, including Kirsten Gillibrand, D-N.Y.and Frank Lautenberg, D-N.J, said they would hold hearings into the matter but conceded the evidence is circumstantial.

Al-Megrahi was convicted in the 1988 bombing of Pan Am Flight 103 to New York -- an attack over Lockerbie, Scotland, that killed 270 people, 180 of them Americans. After his controversial release last year,  reports have surfaced that the Libyan government urged the doctors to give that prognosis, that al-Megrahi is living in luxury and that he could live far longer than previously estimated.

The Sunday Times reported this month that Karol Sikora -- who had given the three-month estimate last year -- now says al-Megrahi could live another 10 years.

When asked whether he is confident the British government will look into it, Menedez said, "We know sometimes it takes enormous pressure to break down the walls...get to the truth."

The senators wrote a letter last week to Nigel Sheinwald, British ambassador to the United States, urging the U.K. government to determine if "inappropriate considerations" led to Abdelbaset al-Megrahi's release.

"There is clear reason to believe that this terrorist was released based on false information about his health," Schumer said in a written statement. "This is especially galling to those of us who believed he shouldn't have been released, even if it had been true that his death was imminent."