Zimbabwe's opposition and civil society groups have expressed anger at a proposed law to monitor communications.
The bill proposes bugging e-mail and phones
The bill proposes a monitoring centre, apparently with Chinese technology, that would eavesdrop on telephone, internet and other communications.
The government says the bill is similar to anti-terror laws elsewhere to protect people from organised crime.
Parliament began public hearings on the Interception of Communications Bill on Wednesday amid heated exchanges.
Communications minister can issue warrants for interception
Police, security and revenue service bosses can apply to minister to issue warrant
Warrants can be issued in case of perceived crime or security threats
Warrants valid for three months, can be extended indefinitely
Right of appeal to minister, not to courts
ISPs must install monitoring hardware and software
"One of the key obligations on internet service providers (ISPs) is to install equipment which would allow them to interface between the ISP and the monitoring service," Jim Holland, spokesman for the Zimbabwe Internet Service Providers' Association, told the BBC News website.
This equipment would have to be installed at the expense of the ISP.
Mr Holland said his organisation would seek clarification on whether the bill applied to all companies that provide internet services to the public.
Asked whether Zimbabwe had the technological capacity to implement the changes proposed in the bill, Mr Holland said: "I would imagine it is now here. There are obviously now close links with the Chinese, who are specialists in the interception of radio and internet communication."
Zimbabwean telephone calls are already monitored.
"The Posts and Telecommunications Regulatory Authority said the interface was already there - all that is required is to connect to the monitoring centre," Mr Holland said.
Monitoring internet communication is nevertheless more complicated than monitoring phone calls, and Zimbabweans using an encrypted overseas-based webmail service would be able to avoid bugging by the authorities in Zimbabwe.
The government has defended the proposal in the name of national security.
"The advancement in technology today means that no one is safe at all from the source of terrorism, mercenarism and organised crime," Brig Gen Mike Sango of the Zimbabwe Defence Force told the hearing.
"A piece of legislation has been long overdue on this particular problem."
Critics raised concerns that the bill does not make provision for decisions to be reviewed by the judiciary.
"An aggrieved person is given a right to appeal to the Minister (of Transport and Communications), who is neither independent nor impartial. He authorises the interception and monitoring in the first place," argued Wilbert Mandinde, legal officer of the Media Institute for Southern Africa in Zimbabwe.
The opposition Movement for Democratic Change agreed: "It seems to give carte blanche - the minister is the judge and the jury, it violates the whole concept of the separation of powers," said MDC legal adviser Jessie Majome.
A special report will be tabled before parliament after the public hearings.
President Robert Mugabe's government already faces criticism for laws that curtail free speech and movement.
Mr Holland said the lack of judicial oversight in the bill was similar to certain provisions of an earlier communications law that were overturned by the High Court in 2004 on grounds of being unconstitutional.