A series of earthquakes with a magnitude of at least 5 have hit the Iran-Iraq border and even rattled Baghdad and parts of the Iraqi countryside, striking in the same area that saw a tremor in November that killed more than 530 people.
There were no immediate reports of injuries or damage in the latest quakes.
The US Geological Survey said five quakes struck near the Iraqi city of Mandali, followed by one that struck near Mehran in western Iran. All struck within an hour of each other.
Iranian state television said people rushed into the streets as the tremors hit.
In Baghdad, people felt a quake shake the Iraqi capital, followed by what felt like aftershocks.
Earthquakes at magnitude 5 can cause considerable damage.
All the quakes struck at a depth of six miles, according to the USGS.
The tremors were very shallow, which causes more ground shaking and potential damage, particularly in places without strict building codes.
Iranian authorities offered similar figures for the earthquakes on state television.
All the information was preliminary and could change as scientists examine the data.
In November, a 7.2-magnitude earthquake struck the same region, killing more than 530 people and injuring thousands in Iran alone.
In Iraq, nine people were killed and 550 injured, all in the country's northern Kurdish region, according to the UN.
Iran sits on major fault lines and is prone to near-daily earthquakes.
In 2003, a 6.6-magnitude quake flattened the historic city of Bam, killing 26,000 people.