The win sent Arsene Wenger's men 10 points clear at the top of the Premiership and left Leeds, Champions League semifinalists just three years ago, marooned in the bottom three and facing an agonising final four games in which to save their Premiership status.

In front of an ecstatic Highbury crowd, Robert Pires opened the scoring after just six minutes before Henry turned on the magic.

In an electrifying performance, Henry registered his fifth Arsenal hattrick and his second in a week following last Friday's triple against Liverpool.

His fourth of the night was his 150th as an Arsenal player and he also became the first man from the club to hit four goals in a Premier League game.

"The boys played some great passes for me to score," said Henry.

"It's always a pleasure to have a group of quality players around you. The most important thing though was that we won and we want to try and remain unbeaten until the end of the season."

Wenger said Henry showed again he is one of the world's deadliest strikers.

"He is one of the best three players in the world," said the coach.

"He is a great pleasure to watch. When the team is on the same wavelength, with power and pace, he is great to watch and he has players of real quality around him."

Leeds boss Eddie Gray tried to hide his disappointment by lavishing praise on the champions-elect.

"They were far superior in every department and when you catch them on a night like this, you will always struggle," said Gray.

"They looked like they could score at will. Henry has such power and pace - the only way to stop him is to punch him and knock him out!"

Arsenal shrugged off the absence of injured first-choice players Freddie Ljungberg and Ashley Cole while Leeds went into the crucial clash missing Seth Johnson and Erik Bakke.

Any hope the Yorkshiremen had of causing an upset disappeared after just six minutes when Pires opened the scoring.

The Frenchman scored with a curling right-foot shot after being set-up by Dennis Bergkamp.

At the other end, Mark Viduka hit a long distant shot and then had a close ranger header easily dealt with by goalkeeper Jens Lehmann before the Gunners added a second goal in the 27th minute.

Bisan Lauren, in for the injured Cole, played a delightful through pass for Henry who sprinted away from a square Leeds backline to score with his left foot beneath the body of Leeds goalkeeper Paul Robinson.

Six minutes later, Henry converted a penalty kick awarded when defender Michael Duberry handled the ball inside the box.

If Leeds thought Arsenal would ease off after the interval, they were to be disappointed when they conceded the fourth of the night.

Gilberto Silva carried the ball out of defence after a Leeds' attack had broken down and played a superbly-timed ball to Henry who once again left his marker behind to get the better of Robinson in another one-on-one.

Sylvain Wiltord almost scored a fifth moments later, but his right foot curler just went wide of Robinson's left-hand post.

However, the fifth goal did arrive in the 67th minute when Pires played a tight pass to Henry who sprinted away from Dominic Matteo and Gary Kelly before scoring with the outside of his right foot even as he stumbled to the floor.