Lawyer Matthias Chang has been detained under the Security Offences (Special Measures) Act (Sosma).

In an SMS message, Chang said he was being arrested on the same grounds as his client, Khairuddin Abu Hassan.

"Just got arrested under Sosma for (Section) 124K and 124L (of the Penal Code). Same as Khairuddin," the text message read.

Section 124K and 124L of the Penal Code deal with sabotaging and attempting to sabotage the state.

Chang's aide told Malaysiakini that he was arrested this afternoon at the Dang Wangi district police headquarters while visiting Khairuddin who has been detained under Sosma for 15 days .

Prior to his arrest today, Chang was questioned by police on Sept 28 and again on Oct 2 as a witness in Khairuddin's case.

Chang had acted as Khairuddin's counsel when the Batu Kawan Umno division deputy chief lodged multiple police reports on 1MDB overseas.

The duo were reportedly scheduled to meet the US' Federal Bureau of Investigation over 1MDB but were barred from leaving the country on Sept 18.

Questioned 1MDB affair

Khairuddin was then arrested under Section 124C of the Penal Code for 'activities detrimental to parliamentary democracy'.

He was released six days later, only to be arrested under Sosma, a law that is supposed to deal with terrorist activities.