Aston Villa's recent revival gathered pace as they heaped more misery on struggling West Ham, who found themselves bottom of the Premiership following this latest defeat.
Graham Taylor's side took the lead through Lee Hendrie before the break but really sparked into life in the second half.
Paolo di Canio gave the visitors some hope when he reduced the deficit with 20 minutes left after Oyvind Leonhardsen had doubled the home side's advantage.
But further strikes from Dion Dublin, his 100th Premiership goal, and Darius Vassell ensured the Hammers remained deep in trouble at the foot of the table.
Both sides made a bright start, but it was West Ham who perhaps should have broken the deadlock in the first 25 minutes.
Jermain Defoe dragged a left-foot shot wide of the far post after turning Steve Staunton before Joe Cole saw his header cleared off the line by JLloyd Samuel.
Defoe had the ball in the back of the net on 28 minutes only for the assistant referee's flag to rule the goal out for offside.
And within 60 seconds, Villa had taken the lead through Hendrie, who had been recalled to the starting line-up.
Gareth Barry's free-kick was chested down by Dublin, and the former England midfielder drilled a low, left-foot shot past David James.
The home side had two chances to increase their lead before the break.
Dublin forced a reflex save out of James before Vassell, back in the side after a toe problem, saw his injury-time volley hit the crossbar.
The action really began to hot up after the interval - and Villa were indebted to Peter Enckelman for keeping them in front.
The Finn rushed off his line to deny Edouard Cisse on 51 minutes before pulling off another top stop to keep out Trevor Sinclair just three minutes later.
Villa could have doubled their lead in between Enckelman's heroics, Leonhardsen's header bravely blocked by Ian Pearce.
But the Norwegian was not to be denied just before the hour mark, beating James at his near post following a dazzling run by Vassell.
Dublin should have made it 3-0 on 65 minutes after James could only parry Tomas Hitzlsperger's 25-yard shot.
But the beanpole striker failed to hit the target with the goal at his mercy.
That miss looked as though it might prove costly when Paolo di Canio reduced the deficit with a header on 70 minutes.
But Dublin made amends when he headed Villa back into a two-goal advantage from a Hendrie free-kick less than two minutes later.
Vassell then heaped more misery on the Hammers by netting number four with 10 minutes remaining.
Aston Villa: Enckelman, Samuel, Mellberg, Staunton, Barry, Leonhardsen, Hendrie (Kinsella 85), Taylor, Hitzlsperger, Dublin (Angel 85), Vassell (Allback 85).
Subs Not Used: Postma, Crouch.
Booked: Staunton, Dublin, Hitzlsperger.
Goals: Hendrie 29, Leonhardsen 59, Dublin 72, Vassell 80.
West Ham: James, Schemmel, Dailly, Pearce, Winterburn, Sinclair, Carrick, Cisse, Cole, Defoe, Di Canio.
Subs Not Used: Repka, Breen, Van Der Gouw, Garcia, Camara.
Booked: Pearce, Cisse.
Goals: Di Canio 70.
Attendance: 33,279.
Referee: C Foy (Merseyside).