A human rights watchdog and families of the victims of the 2009 massacre of 58 people, half of them media workers, in the southern Philippines have criticized the fact that no one has been convicted in one of the worst mass killings in the country's history.

Some of the relatives and journalists marched near the presidential palace to call for an end to impunity on the anniversary of the killings.

Amnesty International expressed disappointment Wednesday that two consecutive administrations have failed to provide effective and swift justice for the victims and their families. It says it has yet to see President Rodrigo Duterte's genuine commitment to protect press freedom beyond mere rhetoric.

The victims included 32 media workers, making the election-related killings the world's largest single attack on journalists.