BANGKOK (AP) — Thai police clashed for the second time in four days on Tuesday with protesters angry over the government's handling of a coronavirus surge and a lack of progress in political reform.

Lines of police, backed by trucks spraying jets from water cannons, fired tear gas and rubber bullets at scores of demonstrators in Bangkok. Protesters threw rocks and fireworks and set fire to a traffic police booth, sending flames and smoke billowing into the sky.

The clashes continued into the evening in the same area -– Din Daeng -– where similar scenes played out last Saturday.

Tuesday’s protest began as a “car mob,” with demonstrators driving to different points in the capital to get around restrictions on public gatherings and minimize the potential for the spread of the coronavirus. Some later broke away, leading to the confrontation with police.

The protesters blame the government for its perceived bungling of the coronavirus pandemic in which Thailand has struggled to suppress a dramatic spike in cases, partly because of the low rate of vaccinations among the population.

But the protests are also part of a wider push for sweeping political change that includes the resignation of Prime Minister Prayuth Chan-ocha, a new constitution and -– most contentious of all -– fundamental reform of the powerful but opaque monarchy.

The protest came on the anniversary of a rally at a university campus last year at which young campaigners revealed a 10-point royal reform agenda. The unprecedented challenge to the monarchy raised the political temperature in Thailand and led to months of rallies and clashes with police and pro-monarchists.

The rallies fell away due to legal action by the authorities, in-fighting among protest groups and the coronavirus resurgence, but began again recently as organizers capitalized on growing public discontent over the state of the country.