Wesley Lowery of The Washington Post and Ryan J. Reilly of The Huffington Post said on Twitter that they were arrested while they were doing work and then released within roughly 45 minutes. Neither was charged.
Lowery wrote that Reilly was "assaulted" as well as arrested. Neither man immediately elaborated on what happened to Reilly, but Lowery described aggressive treatment at the hands of the police: "Officers slammed me into a fountain soda machine because I was confused about which door they were asking me to walk out of," he wrote.
Lowery said the arresting officers refused to provide their names.
Shortly before the arrest, Lowery had written on Twitter, "Police come into McD where me and @ryanjreilly working. Try to kick everyone out." Reilly had posted a picture of what he called "SWAT" inside the fast-food restaurant.
"Asked for ID when I took photo," Reilly wrote.
After his detention, Lowery said the officers "decided we weren't leaving McDonalds quickly enough, shouldn't have been taping them."
CNN reached out to Ferguson police but was not able to obtain immediate comment.
The arrests came amid an already-tense situation between journalists and the authorities in Ferguson, the site of last Saturday's police shooting of an unarmed 18-year-old, Michael Brown.
There have been several reports of reporters and the camera crews being told to leave protest areas, but no reported arrests until Wednesday.
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