On the morning following the battle of Nihawand, Hudheifa bin Al Yaman marched with a strong contingent in pursuit of the Persians. Four miles from the battle-field, at Dareezed a small town, the Muslims found a contingent of the Persian army arrayed for battle. The Persian army was commanded by Dinar.

Hudheifa deployed his army for battle and launched the attack. The Persians could not withstand the charge and they beat a retreat.

The battle of Nihawand was fought at a site eleven miles from Nihawand proper. The army of Dinar now found refuge in Nihawand proper. The Muslim army under Hudheifa advanced and invested the city of Nihawand. The Persians made a few sallies, but they were pushed back each time with heavy losses. Seeing that he could not defend the town against the Muslim army, Dinar surrendered. The Persians agreed to pay Jizya, and a peace pact was drawn up accordingly.

At Nihawand town there was only a small contingent of the Persian army. The bulk of the survivors of the Persian force who had fought in the battle of Nihawand withdrew to Hamadan.

Hudheifa deputed a column under Naeem bin Muqarrin and Qa'qaa bin Amr to pursue the Persian army to Hamadan. When the Persian army came to know that they were being pursued by the Muslims they quickened their pace, and got to Hamadan before the Muslim army could catch them. A huge mule train carrying baggage, however, fell into the hands of the Muslims.

Reaching Hamadan, the Muslims invested the city, and set up posts on all sides to block any aid reaching the besieged army at Hamadan. The Persian forces in Hamadan were commanded by Khusrau Shanum. He soon found that the Persians were no match for the victorious Muslims. Khusrau Shanum surrendered and sought terms. The usual terms were offered and the Persians agreed to pay Jizya Khusrau Shanum also undertook the responsibility to administer the region on behalf of the Muslims.

Khusrau Shanum was accordingly appointed as the Governor of Hamadan under Muslim control. After taking over his office, Khusrau Shanum called upon the people of the region to accept the Muslim rule and pay Jizya. They agreed, and peace was restored.