AMMAN - Syrian forces shelled an opposition stronghold in Hama province, killing 20 people, on Tuesday and hit rebel-held parts of Homs, activists said, as two wounded foreign journalists trapped in the city were reported to have been smuggled safely to Lebanon.President Bashar Assad sent units of an elite armored division, which is led by his brother Maher, into Homs overnight, activists said. Tanks with the words "Fourth Division Monsters" painted on them moved close to the besieged Baba Amro district.Opposition groups say hundreds of civilians have been killed or wounded in the siege of Baba Amro and other rebellious districts in Homs, where terrified residents are enduring dire conditions, without proper supplies of water, food and medicine.Syrian forces on Tuesday launched the heaviest bombardment in their three-week assault on Baba Amro, activists said.Assad, projecting an aura of normality in a land ravaged by 11 months of conflict over his right to power, decreed that a new constitution was in force on Tuesday after officials said nearly 90 percent of voters had endorsed it in a referendum.Opposition groups and Western leaders seeking Assad's removal denounced Sunday's vote as a charade that diverted attention from the violence in Homs and elsewhere.Breaking all "limits of barbarism"Assad's government had "broken all the limits of barbarism". French Foreign Minister Alain Juppe said."And when I see the Syrian president paraded around this voting station in Damascus for this phony referendum, it makes you deeply indignant," he told RTL radio.Juppe said he felt "immensely frustrated" at difficulties in obtaining security guarantees to enable wounded civilians and Western journalists to be evacuated from Homs.American reporter Marie Colvin and French photographer Remi Ochlik were killed in Baba Amro on February 22 in a strike on a house in which Conroy and Bouvier were wounded.The Syrian Arab Red Crescent did manage to evacuate three people from Baba Amro on Monday, but not the foreign reporters, the International Committee of the Red Cross (ICRC) said.The outside world has proved powerless to halt the killing in Syria, where repression of initially peaceful protests has spawned an armed insurrection by army deserters and others."As long as we have not halted the massacres, we are impotent, but we are not inactive," Juppe said.He told the UN Human Rights Council in Geneva on Monday it was time to refer Syria to the International Criminal Court and warned Assad he would be brought to justice.French journalist Edith Bouvier and British photographer Paul Conroy, both wounded last week in an attack in Baba Amro, were now safe in Lebanon, a diplomat and opposition sources said. It was not clear how they escaped.In Hama province, security forces bombarded the town of Helfaya, a hotbed of protests in the uprising against Assad.Activists said the 20 deaths of Sunni Muslim villagers there were among at least 100 killed in the province in the last two weeks in revenge for rebel Free Syrian Army attacks on security forces commanded by members of Assad's minority Alawite sect.The reports could not be independently confirmed. Syrian authorities tightly restrict media access to the country.