The opium trade provided both the money and the incentive for rivals to challenge the central government.

"When we start disarming them, their commanders will be less likely to challenge the government."

"They fear if they challenge the government their aid will be taken away from them."

Many of the governors in Afghanistan abused human rights, challenged the central government and became involved with the drug trade.

"He's in jail because he had the temerity to challenge the existing Russian government."

Frost, challenging the government to act, returned and surrendered himself to the authorities.

"They won't be able to challenge the government," he said.

The Constitutional Court allows private citizens to challenge the government.

Few judges, reading this language, will be likely to challenge the government.

Several rival revolutionary armies were challenging the central government and each other.