A Pakistani anti-terrorism court has indicted seven suspects over last year's attacks in Mumbai, India, which killed 166 people.
The accused pleaded not guilty to the charges on Wednesday, a defence lawyer said, on the eve of the anniversary of the attacks.
Malik Rab Nawaz, a prosecutor in the case, said the men are accused of helping to plan and execute the Mumbai attacks.
The detained include Zakiur Rehman Lakhvi, the alleged mastermind of the November 26 - 29 siege in India's financial capital, and Zarar Shah, an alleged key Lashkar-e-Taiba operative.
Lashkar-e-Taiba is an armed group based in Pakistan, founded to confront India over the disputed territory of Kashmir. It has also been accused of carrying out a spate of deadly attacks on Indian soil over the past decade.
The men could face the death penalty if convicted.
"All seven of them have been indicted, including Lakhvi. The accused pleaded not guilty as evidence is not supported by the charges," Shahbaz Rajput, a lawyer at the trial, told the AFP news agency.
"They have been indicted under the anti-terrorism act and the Pakistani penal code," Rajput said.
India has blamed Lashkar-e-Taiba for the attacks and says Pakistani security agencies have nurtured such groups.
Islamabad has denied any state involvement, but the incident has strained ties between the countries.
Manmohan Singh, India's prime minister, said he welcomes "every step" Pakistan makes to bring the suspects to justice.
But he also called for more action, during a visit to Washington, DC, on Wednesday.
"It is our strong feeling that the government of Pakistan could do more to bring to book people who are still roaming around in the country freely and to dismantle the in
Hafiz Saeed, the head of the Jamaat-ud-Dawa aid group, which is suspected of having strong links to Lashkar-e-Taiba, has not been charged, disappointing many people in Delhi, Prerna Suri, Al Jazeera's correspondent there, said.
Saeed, placed under house arrest by Pakistani authorities in September 2009, is one of India's most wanted men.
India, meanwhile, is trying the lone suspected surviving gunman, Mohammed Ajmal Kasab, who also faces the death penalty if convicted.
Kasab, a Pakistani national, told a court in Mumbai in July that he was one of the attackers.
He gave details of his group's journey from Pakistan on a boat, their subsequent landing in Mumbai, and the rampage that followed as they shot and killed people at a railway station, a Jewish centre and two five-star hotels, including the iconic Taj Mahal.
More than 300 people were injured during the three-day siege across the city.
The assault generated a chorus of public and political demands for government officials to face the consequences for failing to prevent the incident.
Four days after the attacks, Shivraj Patil, India's home minister, stepped down.
In an exclusive interview with Al Jazeera on the eve of the first anniversary of the attacks, Patil said he feels partly responsible.
"For me to say that I cannot be blamed at all is wrong, but for someone else to say that I alone should be blamed is also not correct," he said.
"Intelligence was available. What was not available was the time, the date and the place where [the attack] would take place.
"But to say that it failed totally is wrong. We did inform the concerned authorities in the state that something of that nature was planned, and they should be more careful."