The execution date for an Idaho inmate who has spent nearly 50 years behind bars is set for this week.

Thomas Eugene Creech was served a death warrant with a scheduled execution date for Feb. 28, according to the Idaho Department of Corrections. He was immediately moved to the a cell in the Idaho Maximum Security Institution's F-block, where the execution via lethal injection is scheduled to take place.

If it goes on as scheduled, Creech's execution will be Idaho's first in 12 years.

His attorneys have filed a number of last-minute appeals in four different courts to try to halt the execution. On Feb. 25, a three-judge panel the 9th U.S. Circuit Court of Appeals rejected the argument that Creech should not be executed because he was sentenced by a judge rather than a jury.

Thomas Eugene Creech convicted in multiple killings

Born in Hamilton, Ohio, 73-year-old Thomas Eugene Creech is one of the nation's longest-serving death row inmates.

His name landed on the death row list after he killed a fellow prisoner in 1981 with a battery-filled sock: A disabled man named David Jensen who was serving time for car theft.

Prior to Jensen's death, Creech was convicted of five murders in three states and is suspected of at least a half-dozen others.

It's not clear how many people Creech killed before he was imprisoned in 1974 in Idaho. He claimed at one point to have killed as many as 50 people, but official estimates vary, and authorities tend to focus on 11 deaths.

He was tried for the murder of 70-year-old Paul Schrader in Tucson, Arizona in 1973, but was acquitted by a jury.

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The next year, he killed Vivian Grant Robinson at her home in Sacramento, California, a crime that went unsolved but he confessed while in custody in Idaho. He was not convicted until 1980.

In 1974, while living in Portland, Oregon and working at a church doing maintenance work, he shot and killed 22-year-old William Joseph Dean in 1974. Authorities also believe he fatally shot Sandra Jane Ramsamooj.

He was arrested in 1974, when he was hitchhiking with a girlfriend in Idaho. He shot and killed two painters who had picked them up: Thomas Arnold and John Bradford.

He confessed to a number of other killings while in custody. Some appeared to be fabricated, but he provided information that led police to the bodies of Gordon Lee Stanton and Charles Thomas Miller near Las Vegas, and of Rick Stewart McKenzie, 22, near Baggs, Wyoming.

Creech was initially sentenced to death for killing the painters, but his sentence was converted to life in prison in 1976 after the U.S. Supreme Court barred automatic death sentences. He was placed on death row again after killing Jensen in 1981, where he remains to this day.

Contributing: Associated Press.