How did Pashtun tribal fighters contribute to the beginning of the first India-Pakistan war?

In October 1947, armed Pashtun tribal fighters from Pakistan invaded the princely state of Kashmir, which was then under the rule of the Hindu maharaja, Hari Singh.12

The maharaja had been hesitant to join either newly independent India or Pakistan, hoping to maintain his state's sovereignty. The invasion by these tribal militias—who were backed by Pakistan—forced the maharaja to seek military assistance. In exchange for this aid, he signed the Instrument of Accession, which officially made Kashmir a part of India. This act of accession and the subsequent military intervention by India directly precipitated the first war between India and Pakistan, a conflict that lasted until a United Nations-brokered ceasefire was established in January 1949.132