The violence began around 1 a.m. Monday in Istanbul's Sultanbeyli district, police said, when a vehicle-borne bomb exploded near the police station, wounding at least 10 people.
Then, around 6:45 a.m., assailants opened fire at security forces who were guarding the damaged police station, Turkey's semiofficial Anadolu news agency reported.
By the time the carnage was done, one person had died -- not including two attackers, killed after police returned fire -- and at least 10 others were wounded.
Anadolu also reported that four policemen died and another was injured in a remote-controlled roadside bomb attack Monday morning in southeastern Sirnak province, in eastern Turkey, about 800 miles (1,300 kilometers) from Istanbul.
"A large-scale operation has been launched to find the perpetrators of this terrorist attack," the Sirnak governor's office said.
A military helicopter in the same province also came under attack, killing at least one gendarme private, Turkey's military said, according to the news agency.
Two women attack U.S. Consulate, officials say
Also Monday, two women staged an armed attack on the U.S. Consulate in Istanbul, the Istanbul Governorship said.
Details of the attack were not available, but the governorship said one woman was arrested and the other was being sought. The Anadolu news agency said there were no casualties.
Anadolu said the women belonged to the far-left Revolutionary People's Liberation Party, which is classified as a terror group by Turkey, the United States and the European Union.
In a statement, that leftist group -- also known as DHKP-C -- claimed responsibility for the attack and warned President Recep Tayyip Erdogan's ruling party "who is trying to impress the U.S." of more to come.
"Damn American imperialism and its collaborators!" the group said. "Long live the people's fight!"
The Istanbul Governorship statement said "a long-range weapon and a good amount of artillery" were seized.
Video footage showed police officers with rifles blocking off the streets outside the consulate in the Sariyer neighborhood of the city.
U.S. diplomatic missions attacked before
It wasn't immediately clear if these Monday incidents are connected.
As to the U.S Consulate attack, it's not the first time American diplomatic missions in Turkey have been targeted.
In July 2008, gunmen attacked the consulate in Istanbul. Three Turkish police officers and three gunmen died in the ensuing gunbattle.
In February 2013, an attacker from a leftist group labeled by the Turkish government as a terrorist organization detonated a suicide bomb at the entrance to the U.S. Embassy in Ankara, killing himself and a Turkish security guard, and maiming a Turkish journalist.