Twitter co-founder joins social media chorus from Ferguson

Twitter co-founder and St. Louis native Jack Dorsey was in Ferguson Saturday sending tweets about the protests stemming from the police killing of an unarmed black teenager.

"Feels good to be home. I'll be standing with everyone in Ferguson all weekend #HandsUpDontShoot" the billionaire posted late Friday, before unleashing dozens of Tweets and Vine video posts from protests in the Missouri town.

The hashtag references the death of 18-year-old Michael Brown, who was shot dead by police a week ago, with some witnesses saying the young African American had his hands in the air when he was shot.

Over the weekend the social media maven shared scores of Tweets, many of them video posts from Twitter-owned Vine.

"We're here. My whole family! And @2000F," Dorsey posted, calling Square co-founder Jim McKelvey by his Twitter handle.

Dorsey's tweets from his @jack account chronicled a day of peaceful marching and protests, with photos and videos showing people holding placards, playing drums, singing, and chanting "Hands up, don't shoot!"

He even posted video as rain swept over the evening's events: "Huge lightning storm is our backdrop. #Ferguson"

Brown's slaying by a police officer sparked multiple nights of rioting and looting, with police resorting at times to tear gas, smoke bombs and rubber bullets.

The incident also renewed a national debate about relations between law enforcement and African Americans.

On Saturday Missouri Governor Jay Nixon declared a state of emergency and curfew that would last from midnight (0500 GMT) until 5:00 am for the St. Louis suburb.

He said that the FBI had boosted its presence in Ferguson in efforts to advance the investigation into Brown's death, bringing an extra 40 agents that sought additional witnesses on Saturday.