Quetta, Chaman among cities which felt tremors.
Earthquake occurred at around 5:35am: PMD.
Epicentre of quake was 150km southwest of Quetta.
QUETTA/CHAMAN: An earthquake of magnitude 5.4 struck Pakistan-Iran border and surrounding cities in Balochistan early morning on Tuesday.
The tremors were also felt in several cities including Noshki, Chaman, Qilla Abdullah, Pishin, Dalbandin, Chagai District and Quetta Valley and its surroundings, said Provincial Disaster Management Authority (PDMA).
The 5.4 magnitude earthquake occurred at 5:35am, the seismic centre said, adding that the epicentre of the quake was 150 kilometres southwest of Quetta, and its depth was 35km.
 According to Pakistan Meteorological Department (PMD), the earthquake had a latitude of 29.76N and a longitude of 65.36E.
Meanwhile, another earthquake of magnitude 4.5 struck Balochistan and the epicentre of the quake was 120 kilometres southwest of Quetta.
The second quake occurred at 6:24am.
 Natural disasters such as earthquakes are not uncommon in Pakistan, as the country is situated on the boundary of the Indian and Eurasian tectonic plates.
Large parts of South Asia are seismically active because a tectonic plate known as the Indian plate is pushing north into the Eurasian plate.
Recent earthquakes underscore the importance of disaster preparedness and mitigation measures.