A 16-hour hostage standoff in Australia came to an end after heavily armed police officers stormed a Sydney cafe in the heart of the city's financial center while hostages were seen fleeing amid the sound of explosions, CNN reported.

Two people have reportedly been killed, with one of them being identified as gunman Man Haron Monis, according to Sky News AustraliaAlthough it remains unclear how many people have been injured, the Australian Broadcasting Corp. reported that at least three people were seriously injured.

"Sydney siege is over. More details to follow," New South Wales tweeted.

Early Tuesday, a swarm of at least seven heavily armed police officers quickly made their way into the Lindt cafe under the cover of loud bangs and smoke grenades after a group of about six hostages came out running, according to local news Channel 9. Shortly after the police stormed the café, at least two hostages emerged, appearing visibly shaken.

A few minutes later, a few paramedics were seen entering the café behind police officers with medical packs -- followed by at least two stretchers, ABC News reported.

Monis, a self-proclaimed Islamic "sheikh" from Iran, has allegedly been involved in dozens of counts of sexual assault, according to Australia's 9Newswhich added that the 49-year-old had migrated to Australia in 1996.

"This is a one-off random individual. It's not a concerted terrorism event or act. It's a damaged goods individual who's done something outrageous," his former lawyer, Manny Conditsis, told ABC News. "His ideology is just so strong and so powerful that it clouds his vision for common sense and objectiveness."

After holding the hostages in a popular Sydney café on Monday, the lone gunman had threatened to have planted bombs across the city, multiple media outlets reportedLater, he released videos stating that he wanted an Islamic State flag and a phone call from Australian Prime Minister Tony Abbott.

Earlier in the day, two hostages inside the cafe were seen holding up a flag with Arabic writing on it which read "There is no God but God and Mohammed is the prophet of God," prompting fears that a terror attack was unfolding in Australia's largest city, USA Today reported.

While five hostages were able to flee to safety in the first several hours of the standoff, an undisclosed number of hostages remained in the cafe until the fiery resolution, police officials said.

"We are doing all we can to set you free," New South Wales state police Commissioner Andrew Scipione had said at a press conference hours after the crisis began.

Meanwhile, the armed hostage-taker's motive remains unclear, New South Wales Deputy Police Commissioner Catherine Burn said.

"We don't yet know the motivation of the perpetrator," Australian Prime Minister Tony Abbott said at a news conference earlier in the day.

"We don't know that this is politically motivated although there are some indications that it could be. We have to appreciate that even in a society such as ours, there are people who would wish to do us harm."

The attack was condemned by Muslim leaders in Australia on Facebook, who stated that they "condemn this criminal act unequivocally and reiterate that such actions are denounced in part and in whole in Islam."