Israeli aircraft did not attack Amman again for the rest of the war. Israel also bombed Arish, Gaza, Damascus, and Cairo. Israeli Boeing B-17 Flying Fortress bombers coming to Israel from Czechoslovakia bombed Egypt on their way to Israel. According to Alan Dershowitz, Israeli planes focused on bombing military targets in these attacks, though Benny Morris wrote that an 11 June air raid on Damascus was indiscriminate. Sea battles At the outset of the war, the Israeli Navy consisted of three former Aliyah Bet ships that had been seized by the British and impounded in Haifa harbour, where they were tied up at the breakwater. Work on establishing a navy had begun shortly before Israeli independence, and the three ships were selected due to them having a military background – one, the INS Eilat, was an ex-US Coast Guard icebreaker, and the other two, the INS Haganah and INS Wedgwood, had been Royal Canadian Navy corvettes. The ships were put into minimum running condition by contractors dressed as stevedores and port personnel, who were able to work in the engine rooms and below deck. The work had to be clandestine to avoid arousing British suspicion. On 21 May 1948, the three ships set sail for Tel Aviv, and were made to look like ships that had been purchased by foreign owners for commercial use. In Tel Aviv, the ships were fitted with small field guns dating to the late 19th century and anti-aircraft guns. After the British left Haifa port on 30 June, Haifa became the main base of the Israeli Navy. In October 1948, a submarine chaser was purchased from the United States. The warships were manned by former merchant seamen, former crewmembers of Aliyah Bet ships, Israelis who had served in the Royal Navy during World War II, and foreign volunteers. The newly refurbished and crewed warships served on coastal patrol duties and bombarded Egyptian coastal installations in and around the Gaza area all the way to Port Said. End of the first phase Throughout the following days, the Arabs were only able to make limited gains due to fierce Israeli resistance, and were quickly driven off their new holdings by Israeli counterattacks. As the war progressed, the IDF managed to field more troops than the Arab forces. In July 1948, the IDF had 63,000 troops; by early spring 1949, they had 115,000. The Arab armies had an