An earthquake today shook the flood-hit Dominican border town of Jimani, where torrents of water from a river that spilled its bank killed more than 440 people earlier this week.
There was no immediate word on damage or injuries, but it was impossible to reach the town by phone.
A quake measuring 4.4 on the Richter scale lasted for four seconds, said Jose Luis German, spokesman for the National Emergency Commission.
Such a quake can cause moderate damage in normal circumstances, but the area, along the south-west border between the Dominican Republic and Haiti, suffered torrential floods and mudslides this week.
Government figures put the death toll at 1,100.
The epicentre was on the Haitian side of the border, German said.
There was no way to reach people there in villages under floodwater that are cut off from the world except by helicopters, which the US military has been using to ferry emergency aid to thousands of homeless and hungry survivors.