WARSAW, Poland (AP) — Thousands of disgruntled police, firefighters and other security services are marching through the Polish capital to demand higher pay and more favorable retirement conditions.

Buses carried protesters from across Poland for the march Tuesday, expected to gather some 15,000 participants, including border and prison guards. With a cardboard coffin labeled “Police” and with horns and whistles they are walking to the president’s and the prime minister’s offices to rally there.

Pre-tax monthly earnings in the police range from 2,000 to 4,200 zlotys (470-980 euros; $540-$1,140).