HANOI — Vietnamese police have detained a well-known dissident lawyer, escalating a crackdown on those who speak out against the country’s one-party, authoritarian rule.

Le Quoc Quan was arrested on his way to drop off his children at school Thursday in Hanoi, according to the Vietnamese Redemptorist Church’s website. The state-run Tuoi Tre newspaper reported Friday that Quan was detained for alleged tax evasion.