Turkish police have used tear gas and reportedly fired rubber bullets to disperse civilians trying to stage a gay Pride march in Istanbul in defiance of a ban.

Activists for lesbian, gay, bisexual, trans and intersex rights had vowed to hold the event on Sunday despite being it being officially forbidden by the governor's office for a third year running.

Footage shown by Turkish news organisations showed people running and screaming as tear gas was released.

Activists and news organisations also said rubber bullets were used to prevent crowds from gathering.

However, small ad-hoc demonstrations in support of gay rights were continuing.

Activists had announced plans to gather in the city's central Taksim Square despite the ban, using a Turkish hashtag for "we march."

Police established checkpoints in the area on Sunday, preventing groups from entering Istiklal Avenue and turning back people who they deemed were associated with the march.

Others were told to take over clothing and accessories with rainbow flags.

Activist Mustafa said she was banned from walking through the city centre.

At least a hundred protesters gathered in the nearby Cihangir neighborhood, beating drums and chanting slogans: "Don't be quiet, shout out, gays exist!"

The Istanbul governor's office had refused permission for the march on the grounds of safety and public order fears.

A statement also said the governor's office had not received a valid parade application - a claim rejected by organizers.

Until three years ago, Turkish authorities had regularly allowed Pride marches to take place.

Up to 100,000 people attended Istanbul Pride in 2014 but Turkish police dispersed Pride crowds in 2015 and 2016 using riot-control methods.