Story highlights A former defense official says government agents shot protesters from ambulances

"We have reached a phase of genocide," Mahmoud al-Haj Hamad says

Other ministries have seen budgets cut 30% to pay for the clampdown, he says

Al-Hamad defected to Egypt in December along with his family

Syria's embattled government has been holding jailed dissidents underground and paying pro-government gang members $100 a day to crack down on protesters as it tries to quell months of demonstrations against it, a former defense official said.

Mahmoud al-Haj Hamad was a financial inspector in the Ministry of Defense in Damascus until his recent defection to Egypt. In an interview with CNN this week, he provided a firsthand account of the wheels of repression at work, as seen from his former 12th-floor office.

"I used to see them bringing in blindfolded and handcuffed detainees on buses who are kept in underground prisons, even some built under the streets," he said. During protests in the streets of Damascus, city buses filled with armed gangs left the ministry, flanked by four-wheel-drive vehicles "filled with weapons," Hamad said.

"What is more horrific is the intelligence vans marked with the Syrian Red Crescent insignia that would drive through the protests as ambulances and start firing at protesters," he added.

He blames much of the carnage not Syrian regular troops but on President Bashar al-Assad's intelligence service and the armed gangs he says were recruited to battle protesters.

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"Bashar al-Assad is no longer able to control these human monsters," Hamad said. "We have reached a phase of genocide, and this can't be tolerated under any circumstances."

He said the gunmen were provided with accommodations "and high salaries of about $100 a day." But the nearly 10-month-old crackdown in Syria has cost the government so much that it has had to cut funding for other government ministries by 30%, Hamad said.

Hamad said he supported the revolution from the start, as did many of his colleagues. He said he would even disguise himself to join the demonstrators sometimes.

For a while, he said, "We were hoping the killing would stop and the regime would understand that the revolution will win, and maybe find a way to appease the people. But there was no hope."

As the opposition continued, the ministry began to put restrictions on its own staff, Hamad said. Vacations and travel had to be approved by the intelligence department. So he lied to get out in late December.

"I traveled to Egypt through the airport with the excuse of registering my son in college in Cairo," he said. "When the rest of my family followed me, I announced my defection in protest of what is happening in Syria."