LONDON — The government is set to announce new measures to tackle cyber crime on Friday as Britain's internet and electronic communications network comes under increased attack from hackers and foreign intelligence agencies. As part of the strategy, a new police Cyber Crime Unit will be formed alongside a team at the intelligence agency GCHQ which will fine-tune the country's military capabilities in the virtual world. A joint initiative between the public and private sector will also be launched to deal with cyber threats and develop responses to intrusions and attacks. The GCHQ is expected to help by assisting private companies shore up their cyber defences. These latest measures are part of a £650 million drive to tackle what Cabinet Office minister Francis Maude described as a "real and growing" threat to national security from cyber attacks by organised criminals, terrorists, hostile states and "hacktivists". According to the government, more than 20,000 malicious emails are sent to its networks each month, of which 1,000 are deliberately targeted.