The incidents in Newham and Tower Hamlets also come after the two boroughs were said to be among the areas of London where acid attacks are most common.
In March, a Freedom of Information request to the Metropolitan Police suggested Newham was the London borough with the most recorded acid attacks, with 398 incidents between 20.
"The failings were not on the part of the community - the community has done what it is supposed to do." Mr Siddique said he understood police and security services had an "enormously difficult job" and that terrorists "just need to get lucky once".
A spate of acid attacks has left some Muslim residents of east London afraid to leave their homes.
Fears have been heightened after 21-year-old aspiring model Resham Khan and her cousin Jameel Muhktar, 37, suffered horrific injuries when an attacker squirted acid through their car window in Newham, east London, on 21 June.
The attack on Ms Khan and Mr Muhktar has led to a more than 255,000 people signing a petition calling for tighter restrictions on the sale of corrosive acid.
Stand Up To Racism is also organising a vigil in solidarity with the two cousins, to be held at Stratford Station in east London on Wednesday evening.
A spokesman added that it was not being linked to the attack on Ms Khan and Mr Muhktar, which took place in the neighbouring borough of Newham.
In another attack cited on social media, outside Whipps Cross Hospital in Leytonstone on 8 June, the victim, junior doctor Syed Nadeem, 44, said four masked men on mopeds had rushed towards him shouting: “Give me your money or I’ll cut your throat.” Mr Nadeem was sprayed in the face with acid and suffered burns to his face and arms.
Tower Hamlets had the third highest number of acid attacks, with 84 incidents recorded between 20.
The figures also showed a sharp rise in acid attacks across London as a whole, with 431 incidents in the capital in 2016, compared to 261 in 2015.
He was on tape in a documentary made by Channel 4 several years ago.
"So those concerns I think were in the public domain and highlighted as they should have been.
The incidents included a man of Asian origin having a noxious substance squirted at him while driving in Commercial Road, Tower Hamlets, on Thursday, with the attackers stealing his car as soon as he got out to seek help.