Updated

A Getty Images journalist has been arrested and released in Ferguson as protests over the police shooting death of 18-year-old Michael Brown persisted in the St. Louis suburb.

Photographer Scott Olson said he was "arrested for just doing my job." As with previous arrests of journalists over the past week, no charges were filed against Olson, who by Monday night was back shooting photos.

The arrest came on the first night that National Guard troops were in place at the emergency request of Missouri Gov. Jay Nixon. The crackdown on protesters included a ban on staying in one place, which forced demonstrators to walk up and down the commercial corridor that has become a hub for public gatherings.

Other reporters have also been detained, prompting formal protests by news organizations.