An Albanian rights group has warned against what it called the disproportionate use of police force during protests over a planned luxury resort project linked to US President Donald Trump’s family.

The demonstrations began in late May against a hotel proposal tied to Trump’s daughter Ivanka and her husband Jared Kushner, planned for an environmentally sensitive area along the country’s southwestern coast. The protests have grown into a broader political flashpoint, including calls for Prime Minister Edi Rama to step down.

Protesters gather daily in Tirana, and on Thursday they returned for a second time that week to rally outside parliament and confront lawmakers while trying to block entry. Police broke up hundreds of demonstrators using tear gas, pepper spray and water cannon. Some protesters allegedly tried to push through police lines and threw objects such as eggs, stones and other items.

The police said 15 officers were injured and 25 demonstrators were detained. In a statement obtained by AFP, the Albanian Helsinki Committee said it was concerned about the escalation and that “individual violence cannot justify the disproportionate use of force” by police. It said tear gas was used without warning and that officers used unnecessary force, including batons and punches, even against protesters who were no longer resisting.

The group said the protest was mostly peaceful and that the violence seen in isolated incidents could not be attributed to all demonstrators. It called for an immediate independent and effective investigation, and said the Thursday clashes stood in stark contrast to the largely peaceful daily protests that had drawn thousands earlier in the movement.