The man behind the 2002 sniper attacks in and around Washington DC has been executed after a last-ditch appeal was thrown out.

华盛顿特区以及周边地区2002年狙击案的幕后黑手最后申诉无效，已经被执行死刑。

John Allen Muhammad's lawyers say he was mentally ill, but Virginia Governor Tim Kaine rejected a plea for clemency（仁慈，宽厚）.

On Monday, the US Supreme¹ Court quashed（压碎，镇定） an appeal for a stay of execution（缓期执行）.

Muhammad, 48, was injected with a lethal² drug for the murder of Dean Harold Meyers, one of 10 people killed during the attacks.

Muhammad's accomplice³（共犯，同谋）, Lee Boyd Malvo, who was 17 at the time of the shootings, is serving a life sentence in jail.

The pair killed 10 people during three weeks of attacks in Maryland, Washington and Virginia.

Muhammad was put to death at the Greensville Correctional Center in Jarratt, Virginia.

The procedure took five minutes, and Muhammad died at 2111 (0211 GMT), Larry Traylor of the Virginia Department of Corrections said.

Muhammad did not speak before it began, and seemed quiet and relaxed, Mr Traylor said.

"Mr Muhammad was asked if he wished to make a last statement. He did not acknowledge us or make any statement whatsoever," he said.

He said he was motionless, with his head slightly tilted⁴ to the right as the drug was injected.

His lawyer said that he had eaten chicken in red sauce, followed by strawberry cakes, for his final meal.

Before the execution J Wyndal Gordon, the state attorney appointed to represent Muhammad, said that he would die "with his head held high and no remorse⁵（懊悔）, maintaining his innocence⁶".

He was, said his lawyer, "a martyr⁷（烈士，殉道者） for everything that's wrong with the death penalty".

After the execution, he extended condolences（吊唁，哀悼） to the victims' loved ones, but also to Muhammad's relatives.

"It's just a tragic⁸ situation all around."

Muhammad's legal team says the ex-soldier suffered from Gulf⁹ War Syndrome¹⁰（海湾战争综合症）.

Lawyer Jonathan Sheldon told the BBC's World Today: "A psychiatrist¹¹ examined him and said he's paranoid（妄想狂） and psychotic（精神病） and delusional¹²（妄想的） and gave many examples."

Mr Sheldon also said brain scans of Muhammad had revealed malformations linked to schizophrenia（精神分裂症）.

The shootings left the Washington area gripped by fear, with victims attacked while shopping, outside schools, or just sitting and reading.

Mr Meyers was shot at a petrol station in Manassas, Virginia.

A skilled marksman（神枪手）, Muhammad picked off his targets using a sniper rifle（狙击步枪）, always with a single round and from a distance.

After three weeks, he was arrested at a truck stop, along with Malvo.

Prosecutors¹³ say Muhammad has never shown remorse.

In addition to the 10 people they killed around the Washington area, the pair are suspected of murders in other states, including Louisiana, Alabama and Arizona.

Cheryll Witz was one of several victims' relatives who went to watch Muhammad's execution.

Malvo said he shot her father, Jerry Taylor - at Muhammad's direction - on an Arizona golf course in March 2002.

"He basically watched my dad breathe his last breath," she told the Associated Press news agency.

"Why shouldn't I watch his last breath?"