BELGRADE, Serbia — Soldiers patrol the streets with their fingers on machine gun triggers. The army guards an exhibition center-turned-makeshift-hospital crowded with rows of bunks for those infected with the coronavirus. And Serbia’s president warns residents that Belgrade graveyards won’t be big enough to bury the dead if people ignore his government’s lockdown orders.

Since President Aleksandar Vucic announced an open-ended state of emergency on March 15, parliament has been sidelined, borders shut, a 12-hour police-enforced curfew imposed and people over 65 banned from leaving their homes — some of Europe’s strictest measures to combat the COVID-19 pandemic.

The Serbian leader, who makes dramatic daily appearances issuing new decrees, has assumed full power, prompting an outcry from opponents who say he has seized control of the state in an unconstitutional manner.

Rodoljub Sabic, a lawyer and former state commissioner for personal data protection, says that by proclaiming a state of emergency, Vucic has assumed “full supremacy” over decision-making during the crisis, although his constitutional role is only ceremonial.

“He issues orders which are automatically accepted by the government,” Sabic said. “No checks and balances.”

In ex-communist Eastern Europe and elsewhere, populist leaders are introducing harsh measures including uncontrolled cellphone surveillance of their citizens and lengthy jail sentences for those who flout lockdown decrees or spread false information.

The human rights chief of the Organization for Security and Cooperation in Europe said that while he understands the need to act swiftly to protect populations from the COVID-19 pandemic, the newly declared states of emergency must include a time limit and parliamentary oversight.

“A state of emergency — wherever it is declared and for whatever reason — must be proportionate to its aim, and only remain in place for as long as absolutely necessary,” the OSCE rights chief, Ingibjörg Sólrún Gísladóttir, said in a statement.

In times of national emergency, countries often take steps that rights activists see as curtailing civil liberties, such as increased surveillance, curfews and restrictions on travel, or limiting freedom of expression. China locked down whole cities earlier this year to stop the spread of the virus as India did with the whole nation.

Amnesty International researcher Massimo Moratti said states of emergency are allowed under international human rights law, but warned that the restrictive measures should not become a “new normal.”

“Such states need to last only until the danger lasts,” he told The Associated Press.

In Hungary, parliament on Monday passed a law giving Prime Minister Viktor Orbán’s government the right to rule by decree for as long as a state of emergency declared March 11 is in effect.

The law also amends the criminal code to include two new crimes. It sets prison terms of up to five years for those convicted of spreading false information about the pandemic and up to eight years for those interfering with efforts to contain the spread of the coronavirus, like a curfew or mandatory quarantine.

Rights groups say the law creates the possibility of an indefinite and uncontrolled state of emergency and gives Orbán and his government carte blanche to restrict human rights.

“This is not the way to address the very real crisis that has been caused by the COVID-19 pandemic,” said David Vig, Amnesty International’s Hungary director,

Hungarian Justice Minister Judit Varga said criticism of Hungary’s bill were “political attacks based on the wrong interpretation or intentional distortion” of its contents.

Elsewhere, governments have also adopted extreme measures.

In Israel, Benjamin Netanyahu’s caretaker government passed a series of emergency executive measures to try to quell the spread of the new virus. These include authorizing unprecedented electronic surveillance of Israeli citizens and a slowdown of court activity that forced the postponement of Netanyahu’s own pending criminal trial on serious corruption charges.