A car bomb attack at a police station has killed four people and injured up to 10 people, while the city's U.S. consulate has also come under fire, news agencies have reported.
Reuters, quoting Turkey's Dogan news agency, reported that at a police station in the Istanbul neighborhood had been rocked by a blast early on Monday morning. The agency, quoting the Istanbul's governor's office, added that three attackers and a police officer had been killed in an exchange of gunfire following the explosion.
Istanbul police headquarters confirmed to Dogan that three police officers and seven civilians were wounded in the blast, but gave no death toll.
Al Jazeera said the blast struck at about 1am local time on Monday morning in a quiet part of Istanbul, adding that there was no immediate claim for the attack.
In a separate incident, the US Consulate in Istanbul has been the site of a gunfight between assailants and security personnel, Reuters reported, quoting local media reports. The reports said that one female attacker had been detained while the hunt was on for another woman, the Istanbul governors office told Reuters Monday, overturning earlier stories of a male accomplice.
Later Monday, Reuters reported that four Turkish police officers were killed and one seriously wounded in a blast in the largely Kurdish southeastern town of Silopi on Monday, security sources told the agency.
The attacks come at a time of increasing tensions in Turkey. The country has recently launched airstrikes in Syria, targeting troops of the terrorist organisation Islamic State in Syria and separatist Kurdish troops in northern Iraq.
This is a developing story - please check back for more details.
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