Police have arrested a 51-year-old man after packages containing suspicious white powder were delivered to Parliament House and the ACT Legislative Assembly.
The Belconnen man has been charged with five counts of using the postal service to menace and has been released on bail to face the ACT Magistrates Court on July 26.
Four of the charges relate to the powder scare that forced a three-hour lockdown of the Assembly building on Monday, an ACT Policing spokesman said, while the remaining count related to a similar incident at Parliament House.
Staff in ACT Opposition Leader Jeremy Hanson's first-floor office alerted authorities at about 11.10am after opening a package that contained white powder. More suspicious packages were discovered by staff in the second-floor offices of Chief Minister Katy Gallagher and Greens minister Shane Rattenbury.
A letter inside the package sent to Mr Rattenbury's office raised concerns about the fluoridation of the ACT's water supply.
Sergeant Peter Davis, of Civic police station, said police would investigate whether the incident was linked to a similar scare at Parliament House last Friday.
Nobody except firefighters in hazardous material protection suits were allowed in or out of the building after a lockdown was ordered.
Acting Chief Minister Andrew Barr was working in his office during the incident and was unable to attend a lunch with Prime Minister Kevin Rudd and a meeting with East Timorese President Taur Matan Ruak. Several other MLAs, including Mr Rattenbury, found themselves locked outside the building.
Ms Gallagher is on leave this week.
Students attending a YMCA Youth Parliament program continued to meet in the Legislative Assembly chamber.
Mr Hanson and several members of his staff waited in a ground-level room while firefighters removed the package from his office and sent a sample to a pathology laboratory for examination.
The packages in the offices of Ms Gallagher and Mr Rattenbury were also removed. Some mail in Mr Barr's office was examined but did not contain white powder.
The firefighters who removed the mail had wash-down procedures in the Assembly car park.
The building was reopened at about 2.30pm after tests confirmed the suspicious items were safe.
Mr Barr said police and the fire brigade had kept MLAs and their staff updated throughout the incident on what was occurring.
''We had training in this,'' Mr Barr said. ''We've been through exercises before. This, I guess, was closer to the real thing than any of us have perhaps experienced before.''
Criminal lawyer Peter Woodhouse, of Ben Aulich and Associates, said that using a mail service to perpetrate a hoax was an offence under federal law, punishable by up to 10 years in jail.
Mail routinely goes through a security screening process before being delivered to the Legislative Assembly. In 1996, a man smashed more than 100 windows and panels on the ground floor of the Assembly building, prompting a security upgrade