Martin Landau died from "massive internal bleeding".
Martin Landau
The 'Ed Wood' actor passed away at the age of 89 earlier this month and his death certificate has shown he passed away from hypovolemic shock, which is caused when someone loses a lot of blood.
According to TMZ, who obtained the document, the late star's organs shut down due to the huge amount of internal bleeding.
As well as hypovolemic shock, his death certificate describes him suffering from intra-abdominal haemorrhage, metabolic acidosis and diffuse atherosclerotic vascular disease.
Martin also had a hardening of the arteries when he passed away while hospitalised at UCLA Medical Center in Los Angeles, where he suffered "unexpected complications".
His publicist said earlier this month: "We are overcome with sadness to report the death of iconic actor Martin Landau on July 15th, 2017, at 1.30pm at UCLA Medical Centre, where he succumbed to unexpected complications during a short hospitalisation.
"He had just celebrated his 89th birthday."
Martin is survived by his daughters Susie and Juliet, who he had with ex-wife and 'Mission: Impossible' co-star Barbara Bain - who he married in 1957 and divorced in 1993 - sister Elinor and granddaughter Aria.
The actor shot to fame when he appeared in 'North by Northwest' in 1959, which was directed by Sir Alfred Hitchcock and starred Cary Grant.
He then became a household name with in 'Mission: Impossible', but left the show after three seasons in a dispute over pay.
He was nominated for the Best Supporting Actor Oscar for his role as Abe Karatz in 'Tucker' in 1988 and again in 1989 for his portrayal of an adulterous husband in Woody Allen's 'Crimes and Misdemeanors'.
But he managed to get his hands on one of the famous statuettes in 1994 thanks to his performance as ageing horror movie actor Bela Lugosi in Tim Burton's 'Ed Wood'.
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