Miller, his cameraman, a producer, their driver and a prominent human rights campaigner were arrested by Bahrain authorities while filming a demonstration in the Gulf city on Sunday.
In an audio dispatch from the back of a police car, Miller said the police were very aggressive and violently attacked the group's driver.
The three Channel 4 News journalists were released from detention after nearly six hours and deported to the UK late on Sunday. The driver, named Ali, and human rights activist, Dr Ala'a Shehabi, were released later.
A Channel 4 News spokeswoman said: "We are pleased to confirm that our team is safe and on their way back to the UK. We also have confirmation that the team's driver – who they saw assaulted by Bahraini authorities – and human rights activist Dr Ala'a Shehabi have also been released."
As with journalists from other news organisations, the Channel 4 News team had not been granted accreditation to enter the country to cover the planned demonstrations around the weekend's Formula One race.
Bahrain authorities granted permission only to journalists who regularly cover Formula One, and denied official entry to reporters from Channel 4 News, Sky News, CNN, Reuters and the Financial Times, among others.
The arrests – described by Miller as not particularly pleasant – will expose the Bahraini authorities to further international pressure over its role in attempting to suppress protests in the capital, Manama.
Miller said: "So when we were caught filming a planned demonstration in one of the Shia villages, they [the police] have not been particularly pleasant. They've been very aggressive towards me, my crew and driver and Dr Ala'a Shehabi, a prominent human rights activist.
"We were actually heading back to where we were staying to edit the piece we'd compiled for tonight – we'd met villagers in a Shia suburb off the main city, who were demonstrating night after night."
Bahraini authorities refused to give back the cameras and computers of the Channel 4 News crew, Miller tweeted late on Sunday.
Miller said that his crew were initially refused permission to board a flight out of the country because the group's documentation [was] not in order. The group later boarded a non-British airline flight to London.
