( CNN ) -- Pressure is growing for world leaders to respond to Syria 's brutal crackdown on anti-regime protests . Earlier this week , the United Nations ' Commissioner for Human Rights , Navi Pillay , said more than 5,000 people had been killed in Syria since the uprising began in March . The Syrian government has issued activists in the restive city of Homs an ultimatum : Cease their protests , or face bombardment , prompting fears of an increase in hostilities . Human rights activists have called for an international response to the violence -- but some diplomats have warned that any intervention could make the situation worse . Mousab Azzawi , of the London-based Syrian Observatory for Human Rights , said events in Syria amounted to a `` humanitarian crisis , '' just like that seen in Libya prior to the NATO intervention , and that the situation merited a similar response . `` When the international community went to Libya to protect civilians , were they deceiving [ everyone ] ? '' he told CNN 's Connect the World . `` Because if the principle of protecting civilians is the motivation of the international community , what happens in Syria is no different from what happened in Libya -- it 's the same atrocities , the same tyranny and the same crimes against humanity committed there . '' But Oliver Miles , a former British ambassador to Libya , said there was no comparison between the two countries -- or between Syria and Iraq , another high-profile example of international intervention . `` Syria is different in many , many ways . Iraq was invaded by a foreign government , and seven , eight years later , is in ruins , '' he said . `` Libya was not invaded by a foreign government ; in Libya there was an uprising which so far seems to have succeeded in overthrowing a tyranny and is on the way to building something to replace that tyranny . `` Syria bears no resemblance to either of them . Syria is a larger country than Libya , it 's a more complicated country than Libya , it does n't offer any scope for foreign intervention . '' Refugees seek shelter in Lebanon . Miles said politicians and diplomats were unlikely to take major action against the Syrian regime without backing from the U.N. -- and that such support was unlikely . `` I think the situation in Syria is absolutely dreadful , and if I could think of a way that the British government , or any other government , or the United Nations could intervene effectively , I would be all for it , but I think intervention would probably make things worse , '' he told CNN . `` When foreign air forces started to take part in the Libyan struggle back in March , they had a clear mandate from the United Nations , which meant that under international law , what we did could be argued to be legal . `` There is no possibility whatsoever that we will get a mandate from the United Nations to intervene in Syria as things stand at the moment . '' But Azzawi said such pragmatic attitudes were making the situation worse , accusing foreign powers who failed to act of `` participating in the bloodshed in Syria '' by default . And he said he feared the influence of Syrian military defectors , the Free Syrian Army , on the protests -- unless the fighters were offered international support . `` The numbers of the Free Syrian Army -- without being supported by the international community -- is so small now , and the big risk is when these peaceful demonstrators are tempted by the FSA to hold arms and then we move to a stage of militarizing the uprising , which is a very big risk . `` The people in Syria are trying hard to stick to the principle of peacefulness , '' he said . `` I do n't think that will last forever , but if we have militarization of the uprising , then we will heed to a civil war and I think this is the last thing the international community wants to see in Syria , because any civil war in Syria would be spreading very quickly to the neighboring countries . '' CNN 's Max Foster contributed to this report .
Human rights activists call for an international response to violence in Syria . Diplomats say intervention could make situation worse . U.N. says more than 5,000 people had been killed in Syria since the uprising began .