Sources confirm that Steve Ditko has passed away. Ditko worked exclusively with co-creator Stan Lee specifically on comic books including The Amazing Spiderman as well as Doctor Strange.

Ditko got his start working on a army syndicated comic strip after enlisting in the army post graduation in 1945. From there, after being discharged, he went on to study under Batman artist Jerry Robinson in 1950 in New York City which in turn is how he met editor in chief, Stan Lee. He later went on to create the original Amazing Spiderman which debuted in Amazing Fantasy #15 in 1962 and Doctor Strange which debuted one year later.

Apart from Lee, Ditko is also responsible for going solo for works including Squirrel Girl, Mr. A, Captain Atom and Question, under Charlton Comics. Ditko also worked with Marvel rival DC in 1968 where he created the Creeper, a minor Batman Villain which has made several appearances up to and including the recent 2017 Batman portrayals.

Ditko was found in his Manhattan apartment on June 29. TMZ reported the medical examiner’s cause of death being “arteriosclerotic and hypertensive cardiovascular disease,” or a heart attack caused from clogged arteries. Ditko was 90 years old and is survived by his nephew.