* Mining company executives among those detained
* Prosecutor asks court to keep 11 suspects in custody
* Final funerals held for victims
* Fresh protests in major cities overnight
The detentions were the first of the inquiry and came five days after a fire sent deadly carbon monoxide coursing through the mine in the western Turkish town of Soma, causing the county's worst ever industrial accident.
The disaster has sparked protests across Turkey, directed at mine owners accused of ignoring safety for profit, and at Prime Minister Tayyip Erdogan's government, seen as too close to industry bosses and insensitive in its response.
Police formed a cordon around the court house in Soma as a crowd of onlookers, journalists and relatives of those detained grew steadily. Inside, prosecutors questioned company employees, a police official told Reuters.
One woman said her engineer husband was among those detained inside and one man, whose engineer brother was being held, said dozens of people had been questioned as part of the probe. Both declined to be named.
"We know that we have lost 301 loved ones, but we have loved ones inside as well," the man said.
The governor of Manisa province, Abdurrahman Savas, told reporters that 24 people were being held on what media reports said was suspicion of negligence and "causing multiple deaths".
Prosecutors have sent 11 people before the court with the request that judges remand them in custody, and they continued questioning of the remaining 13 suspects, the reports said. The court was likely to decide on whether to keep the suspects in custody late on Sunday.
The general manager of the mining company, Soma Madencilik, and the plant manager were among those held, broadcaster CNN Turk said, adding that 28 prosecutors had been appointed to the investigation.
A spokeswoman for the company said she had no information on the detentions. A police official confirmed that people had been detained and were being questioned but gave no further details.
The rescue operation at the coal mine ended on Saturday after the bodies of the last two workers were carried out. They were buried on Sunday.
Mourners cried and prayed beside a line of recently filled graves as one of them was buried in Soma.
Holding their palms open to the sky, around a thousand people said "amen" in unison as a white-bearded imam, or Muslim prayer leader, recited verses.
"My only wish and battle will be to make sure Soma is not forgotten," said a written note, signed "your brother", which was left on one grave along with some flowers.
Ramazan, a worker from a mine near the one where the accident occurred, was among those paying his respects.
"My friend lost half of his family. And for what? To make a living," he said. "Accidents can happen of course, but it's an accident when one person, two people die. When 300 people die, its not an accident anymore."
Erdogan has presided over a decade of rapid economic growth but workplace safety standards have failed to keep pace, leaving Turkey with one of the world's worst industrial accident records. The plant manager has denied negligence at the mine which was inspected by state officials every six months.
As the rescue operation wound up, police put Soma on virtual lockdown, setting up checkpoints and detaining dozens of people to enforce a ban on protests in response to clashes on Friday between police and several thousand demonstrators.
Dozens of people were detained on Saturday as hundreds of riot police patrolled the streets while others checked identity cards at three checkpoints on the approach road to Soma.
The checkpoints remained in place on Sunday but those detained, including eight lawyers from the Contemporary Jurists Association, were released by Saturday evening, media reports said.
There were fresh clashes between police and protesters in Istanbul and Ankara on Saturday night amid anger at the government's handling of the disaster.
Erdogan's opponents blame the government for privatising leases at previously state-controlled mines, turning them over to politically connected businessmen who they say may have skimped on safety to maximise profit.
His ruling AK Party said the formerly state-run mine at Soma, 480 km (300 miles) southwest of Istanbul, had been inspected 11 times over the past five years. It denied any suggestion of loopholes in mining safety regulations.