Authorities in South Africa say Islamophobia fuelled two separate attacks on mosques in Cape Town, where Muslim centres of worship were broken into and defiled with pig's blood and a pig's snout.

The Western Cape provincial government said Monday's attack, in which the blood was found smeared over the walls of a mosque in Kalk Bay was linked to an earlier attack on a mosque in Simon's Town, some 15km away, where a pig's snout was left on the entrance gate.

"Both incidents made calculated use of Islamophobic methods," the government said in a statement.

"The similarity of the cases, and proximity of the mosques, raises concerns that the two incidents may be linked."

Achmat Sity, the imam of the 110-year-old Kalk Bay Mosque, urged Muslims to remain calm and called for unity.

"This mosque has been here for over 100 years and this is the first time an incident like this has happened," he told Al Jazeera.

"There have been burglaries in the past, but this was despicable."

The local branch of the ruling ANC party condemned the attacks as "disgusting" and called on South Africans "to stand united in protecting the culture of coexistence".

Pigs are an animal considered ritually unclean in Islam and believers are prohibited from consuming them.

The desecrations came less than a week after a white Western Cape resident posted a message on a community Facebook page calling for mosques to be burned down. The post has since been deleted.

Farid Sayed, the editor of Muslim Views, a national newspaper, said that while the attacks may be isolated in nature, they indicated a failure of some segments of post-apartheid South Africa to fully integrate.

"Racist attitudes are still very deeply embedded in post-apartheid South Africa, all it took was a simple Facebook post to spark this," he said.

"People living in white-only communities believe they have to fight to keep Muslims out, they think they don't have the state's backing.

"This anger - from these racists and bigots - has been heightened by right-wing media outlets that continue to demonise and insult Muslims," he added.

Muslims make up nearly 1.5 percent South Africa's 55-million population and hold prominent positions in politics, academia, trade and elsewhere.

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