Iran has been struck by its most powerful earthquake for more than 50 years, with tremors felt across Pakistan, India and the Middle East.
Last updates:
18:41 GMT: Reuters reports that 35 people have been killed in Pakistan.
17:39 GMT: A military official says 80 people have been injured in Pakistan.
15:41 GMT: Pakistan's death toll has risen to 34, officials told AFP.
14:01 GMT: Pakistan has reported 21 deaths due to the earthquake, according to The First Post.
13:59 GMT: An Iranian provincial governor says there have been no deaths in Iran due to the earthquake, ISNA reported, as cited by Reuters
The epicentre of the 7.8-magnitude quake was near the south-eastern city of Khash, close to Pakistan.
The quake struck deep and in a remote region, apparently limiting casualties.
Iranian state TV said 27 people had been injured, but rowed back on early reports of deaths. However, more than 30 people were killed in Pakistan.
The Pakistani military has been mobilised to help with rescue efforts, officials said.
Two military helicopters carrying medical teams have been sent to the area and troops will support the relief efforts, they said.
The border area has since been shaken by several strong aftershocks.
UN chief Ban Ki-moon said the organisation stood ready to help "if asked to do so". The US has also offered assistance.
Tectonic Summary
The April 16, 2013 M 7.8 earthquake east of Khash, Iran, occurred as a result of normal faulting at an intermediate depth in the Arabian plate lithosphere, approximately 80 km beneath the Earth's surface. Regional tectonics are dominated by the collisions of the Arabian and India plates with Eurasia; at the longitude of this event, the Arabian plate is converging towards the north-northeast at a rate of approximately 37 mm/yr with respect to the Eurasian plate. Arabian plate lithosphere is subducted beneath the Eurasian plate at the Makran coast of Pakistan and Iran, and becomes progressively deeper to the north.
The subducted Arabian plate is known to be seismically active to depths of about 160 km. The frequency of moderate and large earthquakes within the subducted Arabian plate is not high compared with similar events in some other subducted plates worldwide, but several earthquakes have occurred within this slab in the region of today's event over the past 40 years, including a magnitude 6.7 shock 50 km to the south in 1983. In January of 2011, a M 7.2 earthquake occurred approximately 200 km to the east, in a similar tectonic environment to the April 16 earthquake.
http://earthquake.usgs.gov/earthquak...0g7x7#shakemap http://www.google.org/publicalerts/a...=IT&source=web http://www.bbc.co.uk/news/world-middle-east-22168202