the escorts, and as the escorts returned fire she withdrew, giving Cero a chance to escape unharmed. On 23 February 1944, Peto headed for Langemak Bay to refuel and obtain spare parts, arriving there on 27 February. On 1 March, she headed for her patrol area again, and on 3 March made an unsuccessful attack on a Japanese merchant ship. The next day, she fired six torpedoes at a cargo ship and then went deep to listen as escorts were near. He crew heard two hits, followed by a loud, deep explosion. Three minutes later breaking-up noises began, and her crew heard splashes from debris falling in the water for several minutes. The escorts dropped 13 depth charges before giving up. Peto had sunk Kayo Maru. On 16 March, Peto set course for Midway Atoll in the Northwestern Hawaiian Islands, where she arrived on 25 March 1944. She departed for Pearl Harbor, Hawaii, the same day, arriving there on 29 March 1944. Sixth war patrol On 28 April 1944, Peto, along with the submarine and an escorting surface warship, departed Pear Harbor for her patrol area south of Formosa. She departed from Midway on 2 May 1944, with Perch and the submarine joining her wolf pack. Arriving in her patrol area, Peto began looking for shipping worthy of her torpedoes. She made only six ship contacts during the entire patrol and could obtain a favorable attack position on any of them due to Japanese aircraft in the vicinity or shallow water. She returned to Midway on 15 June 1944 and later that day departed for Pearl Harbor with the submarine , arriving on 19 June. June–October 1944 On 21 June 1944, Peto headed for San Francisco, California, for major alterations at the Bethlehem Steel Company shipyards. On 29 September 1944, Peto headed westward again, reaching Pearl Harbor on 7 October 1944 and arriving at Midway Atoll on 27 October. Seventh war patrol At Midway, Peto joined the submarines and , forming a wolf pack designated Task Group 17.13. The submarines arrived in their assigned patrol area in the Yellow Sea 9 November 1944. On 12 November 1944, Peto heard a loud explosion and saw a large flash. A burning ship with hull down was seen to the east and it was assumed the submarine , which was also in the vicinity, had connected. Peto sent her crew to their battle