GENEVA (Reuters) - The Belarus government has returned to a policy of large-scale repression, causing a dramatic deterioration in human rights, according to a report published on Monday for submission to next month’s session of the U.N. Human Rights Council.

Last month the United States extended sanctions relief for Belarus for a further six months, part of an effort to engage with its veteran leader President Alexander Lukashenko. The European Union last year ended five years of sanctions against Belarus.

The report by the Council’s Special Rapporteur on Belarus, Miklos Haraszti, called on the international community to remain vigilant on human rights in Belarus.

“The human rights situation in Belarus has seen a dramatic deterioration,” it said.

It said a suppression of peaceful protests in March was the severest crackdown since 2010, and ended a brief period where the government had been reticent about using force.

“The Special Rapporteur regrets that his warnings about the dangers inherent in the systemic character of the entrenched oppressive laws have proved right,” the report said.

The crackdown in March followed protests against a law imposing a tax on those not in full-time employment, popularly known as the “law against social parasites”.

Haraszti’s report said more than 900 people were detained “on trumped-up charges”, including opposition leaders, human rights defenders, journalists and foreign visitors.

“It is another instance of the cyclical pattern of the human rights policy of the authorities,” the report said.

“Over the past two decades, they have repeatedly returned to repression, following brief periods of relative liberalization, while leaving intact the legal order that was purposefully developed to suppress several basic human rights.”

Belarus also executed four people in 2016, the highest since 2008 and a return to the death penalty after the European Union partly lifted its sanctions in February 2016.