Police in Greece have used tear gas on pensioners who were protesting against cuts to their income from the state.
Some of the hundreds of protesting pensioners tried to topple a police bus, while others attempted to break through riot police lines.
Due to austerity reforms, pensions in Greece have been cut repeatedly and they are now worth 25-55% less than they were before the economic crisis.
Pensions are a sticking point in Greek dealings with international creditors.
Alexis Tsipras's government has to make more than €1bn ($1.12bn) in savings through pension reforms under the terms of a bailout from international lenders.
But a survey published by the National Pension Network last week suggested that nearly half of pensioners now have a monthly income below the official poverty line.
"We can't live on €400 ($450)," the protesters chanted as they marched.
"Let the rich pay for the crisis" was another favoured chant.
Monday's protest was timed to coincide with a draft budget, which projects economic growth of 2.7%, being heard in parliament.
But some of the protesting pensioners mocked that suggestion.
"It's just a big fat lie," said Vassilis Bardas, 76. "This government are the biggest liars of all the others put together."
After the protest, Nikos Toska, minister for citizens' protection, moved quickly to decree that tear gas was banned from being used against "protests by pensioners and workers".