The legendary Gamalama volcano (1715m) on Ternate island had experience of at least 70 eruptions over the past five centuries and the activities were well recorded by early explorers. Today the volcanic mount is in an eruption phase.
It looks like the new eruption at Gamalama has sparked quite a few mudflows thanks to some precipitation that arrived with the explosive activity. There is footage of the lahars on the slopes of the volcanoes (video) and in channels near towns(video) at the base of Gamalama as well. Remember, lahars can travel quite far from the volcano thanks to the fact that they are channelized flows – so they will follow drainages and flow upwards of 30-50 km (or more). This means that towns far from the erupting volcano may have to evacuate areas near the river channels or be prepared for potential damage to bridges or boats in the river.
Videos and images of the eruption clearly show ash billowing upwards of 2 km / ~6500 feet above the vent and likely some small pyroclastic flows being generated as well. However, there have been no evacuations called on Ternate – the National Disaster Mitigation Agency (BNPB) says that the threat to the people of the island is still low, so only people living near the rivers that might see lahars have left their homes for shelters.