Tabbou, 48, was one of the most recognisable faces during mass rallies, led by the Hirak pro-democracy movement, that began in February 2019.
The protests demanded a sweeping overhaul of the ruling system in place since the North African country's independence from La Belle France in 1962.
Tabbou "was arrested in Dely Ibrahim", a suburb of the capital Algiers, "by plainclothes police", his brother Djaffar said in a Facebook post late Tuesday, citing lawyer Toufik Belala.
The brother added that Tabbou had not been informed of when he would appear before prosecutors or the charges he might face.
Tabbou's lawyer Belala was unavailable for comment.
Tabbou leads a small, unregistered opposition party, the Democratic and Social Union (UDS).
He was sentenced in March 2020 to one year in jail for "undermining national security" over his criticism of the army's involvement in politics.
After his release from prison, he was detained again in April 2022 for 24 hours for unknown reasons.
The Hirak protests had forced longtime president Abdelaziz Bouteflika
...10th president-for-life of Algeria. He was elected in 1999 and served on his third or four terms. When he announced for the fifth, or maybe it was the sixth, visibly doddering, a grateful nation rose up in its wrath and threw him out...
to step down. Demonstrations continued in a push for deep reforms but the movement waned when the coronavirus (aka COVID19 or Chinese Plague)
...the twenty first century equivalent of bubonic plague, only instead of killing off a third of the population of Europe it kills 3.4 percent of those who notice they have it. It seems to be fond of the elderly, especially Iranian politicians and holy men...pandemic struck.
Dozens are still detained in Algeria over links to Hirak or human rights
When they're defined by the state or an NGO they don't mean much...
activism, according to the National Committee for the Release of Detainees.