Their deaths bring to 25 the number of civilians cut down in the Israeli offensive, of whom at least 14 are women and children, the youngest a month old.
In southern Lebanon the Hizbollah fired another 20 Katyusha rockets back at Israel, wounding several civilians. Israel did not give precise figures.
The sixth day of Israel`s operation, which it says is intended to force the Lebanese government to disarm the Hizbollah, opened before dawn when two helicopters flew over the Ein el Helweh camp and fired two missiles at the house of Mounir Maqda, a Palestinian official who broke with the PLO leader because he disagreed with the Oslo accord between the PLO and Israel.
Mr Maqda was not hurt, but his three-year-old son Mazen was reported to be badly injured and a married couple were gravely wounded when one of the missiles hit their neighbouring house.
Osama and Samia Osman were taken to the Hammoud Hospital in Sidon where they were yesterday in critical condition with shrapnel wounds to the head and upper body. Dr Ghassan Hammoud, the director and owner of the hospital, gave the Independent a set of hospital records which show that in the past six days, his doctors have tended 88 wounded civilians. The figure suggests that the official tally of 166 wounded in all Lebanon may be a serious underestimate. One of Mr Maqda's bodyguards was also reported to have been wounded in the missile attack - the only militia man reported to have been injured during the day. A married couple were also wounded by shell fire in the village of Tibnin. But still not a single Hizbollah guerrilla appears to have been killed.
Two other civilians were wounded when an unnamed woman died in the Israeli air raid at Baalbek which the Israelis said was aimed at a Hizbollah office. They used the same description of the helicopter missile attack on Beirut's southern suburbs which killed the two year old girl in mid-afternoon.
Yesterday morning, Israel's proxy militia radio station in southern Lebanon began threatening civilians in Tyre, warning them to leave their homes if `terrorists' lived near them and created a miniature version of the mass panic that gripped Tyre at the weekend. By nightfall Sidon's streets were almost empty.
A US proposal aimed at ending the fighting seemed to be over almost before it began when Lebanese Prime Minister Rafik al-Hariri said it was difficult for Beirut to accept some of its terms. US Ambassador Richard Jones had called for the revival of a 1993 understanding barring attacks against civilian targets on both sides of the Lebanese-Israeli border as a first step.