BANGKOK—Antigovernment protesters blocked off many of the roads leading to the commercial and business core of Thailand's capital on Monday, in their latest bid to force Prime Minister Yingluck Shinawatra from office and scuttle elections scheduled for Feb. 2.

The scene in the center of the city resembled a lazy Sunday rather than a rush-hour Monday. Demonstrators blocked off a series of intersections around the city, shutting the flow of traffic into the area, which includes some of Bangkok's busiest shopping hubs. Many commuters opted to take public buses or the city's rail links to get to work, while others chose to ride passenger ferries along a canal that bisects Bangkok.

Some offices closed for the day, along with many schools and colleges, though trading on the country's stock exchange opened as usual.

Authorities on Sunday issued an order prohibiting protesters from blockading Bangkok, a possible prelude to stepping up security measures, but protesters had occupied some areas by Sunday evening and showed no sign of leaving Monday.

Tensions have been building in the run-up to what protest leader Suthep Thaugsuban has billed a final showdown to drive out Ms. Yingluck and to install a nonelected government to carry out what he said are needed political overhauls. That is necessary, he said, to eradicate a pattern of corruption and vote-buying from Thai politics before another election can be held.