President Mahmoud Abbas has asked the Palestinian attorney general to investigate a senior Hamas official who was caught trying to smuggle nearly 1 million dollars into the Gaza Strip, a senior Abbas adviser said Friday. "President Abbas has sent the money and the file to the attorney general," said the Abbas adviser, legislator Saeb Erekat. "It has become a legal case that requires an investigation." Earlier Friday, the senior Hamas official, Sami Abu Zuhri, was caught trying to smuggle â‚¬639,000 into Gaza from Egypt, a possible sign of how desperate the cash-starved Hamas government is for money. Abu Zuhri was stopped at the Palestinian-controlled Gaza-Egypt border. Dozens of armed Hamas activists gathered outside the border crossing in a tense standoff after officials, loyal to President Mahmoud Abbas, confiscated the money. Dozens of Hamas gunmen blocked the crossing as Abu Zuhri was escorted out of the terminal by Ghazi Hamad, a Hamas government spokesman, and a political adviser to Prime Minister Ismail Haniyeh of Hamas. Julio De La Guardia, a spokesman for a European Union contingent that monitors the crossing, said travelers crossing through Rafah must declare all sums over $2,000 and explain its origin. "He (Abu Zuhri) did not declare that money, he tried to smuggle it," De La Guardia said. Abu Zuhri's attempt to bring in such a large sum could be an indication of how desperate the cash-strapped Hamas government is to bring in money to pay long-overdue salaries. "We are upset to be dealt with this way at a time when the Palestinian people are suffering from siege and starvation," Abu Zuhri told Al-Jazeera. Late Thursday night Palestinian Authority police were engaged in a firefight with Hamas activists in Gaza City. Two policemen and one Hamas activist were wounded in the gunfire. Residents said Hamas gunmen had surrounded the central police station in Gaza City and opened fire, according to an Israel Radio report. Hamas activists belonging to the organization's new security force then rushed to the scene to join the firefight.