A Turkish court detained five people overnight on suspicion of links to a March 13 suicide bombing in Ankara that killed 35, the Anatolia news agency reported on Saturday.
The arrests came just hours before another suicide attack in a busy Istanbul shopping street which killed four and wounded 20, the city governor said.
It was not immediately clear whether the bomber, who was also killed, was listed among the four dead.
The five people arrested overnight stand accused of "an attack on Turkish unity and on the Turkish people," Anatolia said, citing an Ankara court which ordered the detentions.
The arrests came as Turkish airforce planes continued to bomb outlawed Kurdistan Workers' Party (PKK) hideouts in mountains across the Iraqi border, an army statement said.
The army said 30 planes took part in the bombings which hit the area around Sinat and Haftanin and Gara.
The Kurdistan Freedom Falcons (TAK), a radical Kurdish group with ties to the PKK, claimed responsibility for the March 13 blast.
Turkish officials accuse the group of being a front for attacks by the PKK, which is listed as a terror group by Ankara and its Western allies and which launched an insurgency against the Turkish state in 1984 targeting greater autonomy for Kurds.
The group has support bases inside northern Iraq.
AFP
Sat Mar 19 2016
The five people arrested overnight stand accused of "an attack on Turkish unity and on the Turkish people. -Filepix
Millions in Cuba still without power as major outage persists
Millions of Cubans remain without electricity because of a prolonged outage at the main power plants on the island, Anadolu Agency reported.
Surge in Gaza violence increases famine risk, monitor says
About 1.84 million people across the besieged Palestinian enclave are living through high levels of acute food insecurity.
Israel pounds Beirut and Gaza after rockets hit Israel's north
A drone was launched at Prime Minister Benjamin Netanyahu's holiday home.
Elon Musk promises to award $1 mil each day to a signer of his petition
He awarded a $1 million check to an attendee of his event in Pennsylvania aimed at rallying supporters behind Donald Trump.
Former special forces commander Prabowo to take up Indonesian presidency
Indonesia's Prabowo Subianto will take over as president of the world's third-largest democracy after sweeping the country's election with policies like free meals for school children
Father of Malaysian Islamic banking, Abdul Halim Ismail passes away
His dedication and pioneering spirit played an important role in shaping the journey of Bank Islam as well as leaving a lasting impact on the development of Malaysia's Islamic finance industry.
Zayn Malik postpones US tour dates after One Direction bandmate Liam Payne's death
Payne, 31, died on Wednesday after falling from a third-floor hotel room balcony in Buenos Aires, shocking fans of the boy band.
Why voters in a handful of swing states will decide the US presidential election
The contest will almost certainly be decided by just tens of thousands of voters a tiny fraction of the populace in a handful of states.
INSIGHT - Sudan's war risks 'lost generation' of children
A devastating crisis is unfolding in Sudan, where the most vulnerable members of society children are bearing the brunt of the violence.
Who is Prabowo Subianto, incoming president of Indonesia?
A wealthy ex-general with ties to Indonesia's popular outgoing president and its dictatorial past, looks set to be its next leader.
Trump says he would impose tariffs on China if China went into Taiwan
Republican presidential candidate Donald Trump said he would impose additional tariffs on China if China were to "go into Taiwan,"
Iran's supreme leader says Hamas leader's death will not halt 'Axis of Resistance'
The "Axis of Resistance", built up with years of Iranian support, includes Hamas, the Lebanese Hezbollah group, the Houthi movement in Yemen, and various Shi'ite groups in Iraq and Syria.
Putin says Russia willing to seek compromises between Iran and Israel
Russia is ready to help seek compromises between arch-foes Israel and Iran, President Vladimir Putin said on Friday, saying these would be difficult but possible.
What proposals will Russia push at the BRICS summit?
The proposal is also to establish a BRICS reinsurance company to allow uninterrupted shipment of goods and key commodities between members.
Indonesia's free meals plan in the spotlight as Prabowo readies for office
Prabowo calls the programme one of the main drivers of economic growth, eventually set to add an estimated 2.5 million jobs.
Astro AWANI's revamped English news website, AWANI International, launches on Oct 21
Astro AWANI's revamped English platform delivers in-depth global news and expert analysis to keep you informed on key developments.
Israeli strikes kill 33 people in Jabalia refugee camp in Gaza, medics say
Residents of Jabalia said Israeli tanks had reached the heart of the camp after pushing through suburbs and residential districts.
Liam Payne's ex-partner calls for media restraint after 'painful' death
Cheryl Tweedy used her statement to urge the media to remember they had a seven-year-old son, Bear, who could read the reports.
Analysts: Indonesia's strong MoF leadership team to boost investor confidence
Sri Mulyani Indrawati as head of Indonesia's Ministry of Finance is expected to instil confidence among investors.
Biden offers both a carrot and a stick to Israel as his term nears an end
Israel has frequently resisted US advice and has caused political difficulties for the Biden administration.