LISLE, Illinois (REUTERS) - Hundreds of people on Saturday attended the funeral of Sandra Bland, a black woman found dead in a Texas jail cell days after she was arrested following a minor traffic offence, an incident said by activists to be yet another example of police brutality towards minorities.

Mourners including local politicians lined up for more than an hour outside the DuPage African Methodist Episcopal Church in Lisle, Illinois, to file past an open casket and attend the funeral.

"This is not a moment of defeat, this is an hour of victory... We are not funeralising a martyr or a victim, we are celebrating a hero," said Reverend James Miller, who led the funeral service.

He asked everyone to pressure the government for a federal investigation into Bland's death.

Bland, 28, was pulled over by a white Texas state trooper on July 10 near Prairie View, Texas, north-west of Houston, for failing to signal a lane change.

After the stop escalated into an altercation between her and the trooper, Bland was taken into custody and charged with assaulting an officer.

She was found hanging in her jail cell on July 13 with a plastic trash bag around her neck.

An autopsy preliminarily confirmed an initial finding by a medical examiner that Bland's death was a suicide.

The trooper, who has been placed on desk duty for violating protocol in the arrest, pointed a stun gun at Bland and said he would drag her out of the car.

Another video, taken by a bystander, showed the officer forcing Bland to the ground as they argued.

Illinois politicians US Senator Dick Durbin and US Representative Bill Foster spoke at the funeral and drew applause when they called for a full investigation of Bland's death.

An overflow crowd was directed to the church's basement to watch the funeral on a live video feed.

Many sang, clapped and danced after viewing Bland's body.

Her former sorority sisters from her alma mater, Prairies View A&M University, read an obituary highlighting her religious faith and her blogs about social injustice, race politics and police brutality.

Bland, originally from the Chicago area, had been about to start a temporary job at Prairie View A&M, when she was stopped by the trooper.

Bland's family acknowledged she had posted on social media about struggling with depression but has disputed the suicide ruling.