Ankara, Turkey (CNN) -- A top Turkish official apologized for the "police aggression" that fueled nationwide protests against Prime Minister Recep Tayyip Erdogan as trade unions threw their weight behind the demonstrations Tuesday.

The 240,000-member KESK confederation of public-sector workers called for a two-day strike to protest what it called the "fascism" of Erdogan's ruling Justice and Development Party. The protests began over plans to replace an Istanbul park with a new development, but spread nationwide after a heavy-handed crackdown by police.

After chaotic scenes in the streets Monday that continued late into the night and sent tear gas wafting through the air, the situation was relatively calm Tuesday in Istanbul's Taksim Square, near the park where the protest movement began, and in the capital Ankara.

Riot police around Ankara's central Kizilay Square brought in armored vehicles topped with water cannon in a show of force Tuesday evening, but the demonstrations throughout the day were calm.

One of Turkey's big trade union groups is staging a two-day strike to support continuing anti-government protests in a number of cities.

The left-wing Kesk trade union confederation, representing some 240,000 workers, accused the government of committing "state terror".

Protests and clashes with police continued into the night on Monday.

A second death in the protests has been confirmed by the governor's office in the southern city of Antakya.