"Throughout the course of the day and into this evening, Congresswoman Tubbs Jones' medical condition declined," Sheil said in a statement from the clinic and Tubbs Jones' family.
The liberal Democrat, first elected in 1998, suffered the hemorrhage while driving her car in Cleveland Heights Tuesday night, said Dr. Gus Kious, president of Huron Hospital in East Cleveland.
She had suffered "a very serious brain hemorrhage" caused by an aneurysm that burst in an inaccessible part of her brain, he said.
A brain aneurysm is a bulge in an artery in the brain. It can leak or rupture, causing bleeding in the brain.
Tubbs Jones represented the heavily Democratic 11th District and chaired the ethics committee in the House. She was the first black woman to serve on the powerful Ways and Means Committee, where she opposed President Bush's tax cuts and his efforts to create personal accounts within Social Security.
Several news organizations, including The Associated Press, had earlier reported that Tubbs Jones had died. The AP cited a Democratic official.
The reports prompted Sen. John Kerry to issue a statement mourning her passing.
Associated Press writer Andrew Taylor in Washington contributed to this report.