Hundreds marched from Padang Merbok to Parliament this morning to demand for the release of Bersih chairperson Maria Chin Abdullah.

Led by activists from various women's rights organisations, the crowd, clad in purple and Bersih yellow, started walking at 10.45am and arrived outside Parliament about 20 minutes later.

Among those in the front line were National Human Rights Society (Hakam) chairperson Ambiga Sreenevasan and Global Bersih steering committee member Ivy Josiah.

The 'Walk for Maria' was organised by her friends and supporters to submit a memorandum to Prime Minister Najib Abdul Razak, who is currently in Peru, to protest against her detention under the Special Offences (Security Measures) Act 2012 (Sosma).

The crowd stopped a few hundred metres outside the Parliament gate and several representatives were allowed in to submit the memorandum to cabinet ministers.

For almost two hours, the crowd who stood by the roadside kept up their chants of "Hidup Wanita!" "Bebas Maria!" and "Mansuh Sosma!" - raising their voices and placards every time an official car passed through.

Several others shouted "Shame on you Najib" while pointing at the Parliament building.

Several opposition lawmakers who were in the House also came out to show their solidarity with the group.

At around noon, a group of secondary school students who were visiting Parliament walked out, at first appearing taken aback but quickly joined in the crowd's chants, waving, pumping their fists and giving them the thumbs up.

A group of about 30 police officers stood guard along the road leading to Parliament.

The representatives who went in left the building at close to 1pm.

Speaking to reporters, Ambiga said they have submitted a memorandum with three demands - to free Maria, to return Bersih's seized assets, and to abolish Sosma - to Ministers in the Prime Minister’s Department, Shahidan Kassim and Nancy Shukri.

"He (Shahidan) just said, 'We'll look into it. We will listen to the women's voice'," she said, adding that Nancy had promised to do her best to raise the issue.

Bersih steering committee member Fadiah Nadwa Fikri, meanwhile, stressed that they will not be intimidated by any form of threats.

"We will continue to fight for free and fair elections.

"This is our promise. We will not give up or give in," she stressed.

Others who went in included G25 founder Noor Farida Ariffin, student activist Anis Syafiqah and C4 executive director Cynthia Gabriel.

Under Sosma, Maria can be detained for up to 28 days without trial.

She is also being investigated under Section 124C of the Penal Code for alleged involvement in activities detrimental to parliamentary democracy.