ATHENS, Greece — Greek police fired tear gas and pepper spray at protesting pensioners who challenged a cordon near the office of Prime Minister Alexis Tsipras, whose left-wing government faces mounting pressure over planned austerity measures.

More than a thousand people, some of them with canes, took part in Monday’s rally. Protesters chanted “Shame on you, shame on you!” with one group of elderly demonstrators trying to tip over a riot police bus, triggering the police response.

Protesters ran, with one gray-haired man falling to his knees and coughing and several others appearing to be in distress.

No arrests or injuries were reported. In response to opposition party criticism, police said they were indefinitely suspending the use of tear gas at “rallies of worker and pensioners.”

Greece’s left-wing government has imposed new cuts on pensions this year as part of its bailout commitments to international lenders, with the International Monetary Fund pressing for tougher measures.

The latest round of cuts follows six years of bailout-related austerity measures, while nearly a quarter of Greeks remain unemployed and no longer eligible for state benefits.

“This is a fight for our life. The country has been driven to desperation,” pension protest organizer Dimos Koumbouris told the Associated Press.

“They have torn our income to shreds — taking money that people earned with hard work. We have to protest today and keep protesting. There’s no other option.”

Years of cuts have pushed nearly half of pensioners’ monthly income below the official poverty line, according to a survey published last week by the National Pension Network, an organization that represents Greece’s main retiree associations.

And 52 percent of Greek households rely on pensions directly or indirectly to meet monthly expenses, the survey found.

Prime Minister Alexis Tsipras’ government is facing mounting public discontent as it prepares to approve a new round of unpopular measures in the winter — including loosening employment rights and mortgage protections.

His government is pinning its hopes on a strong rebound in the economy next years after eight years of recession or near-zero growth.

According to preliminary 2017 budget figures released Monday, Greece is set to post growth of 2.7 percent in 2017, from a 0.3 percent contraction this year.

But unemployment is forecast to remain high next year, at 22.4 percent, and the national debt at a staggering 175 percent of annual output — 318.7 billion euros ($358 billion) — from its peak of 179 percent in 2016.

An opinion poll published Sunday found 85 percent of Greeks believed the country was headed in the wrong direction, with 51 percent backing an early general election, and 42 percent picking the conservative opposition leader Kyriakos Mitsotakis as most suited to be prime minister, compared with 23 percent backing Tsipras.

Nicholas Paphitis and Srdjan Nedeljkovic in Athens contributed. Follow Gatopoulos at

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