Barely a month after they tied the knot, Aleya (not her real name) and her husband got the shock of their lives.

Photos and videos of some private moments of the 21-year-old woman and her former boyfriend, Monirul Islam Moni, were sent to her husband, his family members and friends through social media, putting the marriage in jeopardy.

Moni had copied the photos and the videos in her phone in 2013 when the two were in a relationship. He stole the memory stick and kept it with him even after they broke up.

He spread the photos and the videos after the girl from the capital's Lalbagh got married on this January 12 to an engineer, according to the statement of a case filed over the incident.

"Devastated, my daughter rushed to my home and burst into tears before telling me everything," the girl's father, who filed the case with Lalbagh Police Station, told The Daily Star.

Police arrested Moni immediately and recovered the memory stick. The marriage was saved, he said, adding the accused was behind bars.

It is not the only case where a girl becomes a victim of cyber crime. In fact, such incidents are taking place frequently in the city and elsewhere, said police.

According to the Cyber Security and Crime Division of the DMP, 70 percent of cyber crime victims were women and 57 percent of them were between 18 and 25. Thirteen percent of the victims were below 18.

The unit came up with the findings after analysing 666 cases and complaints over cyber-related offences filed with different police stations in the capital since 2016, when the division started working as part of the Counter Terrorism and Transnational Crime (CTTC) unit.

In a similar incident, a girl was harassed after she had lost her smart phone, logged in with her email ID, in October last year.

As she called her number, she came to know that a man named Ridwanul Haque found the phone. She requested the 32-year-old man to sign out from her email. She also gave the man her phone's password hoping that he would sign out from the email.

However, the man downloaded her personal photos from her email account and threatened her to circulate them on social media if she did not have an affair with him, according to a complaint filed with Adabar Police Station later.

On being informed, police detained the man and settled the matter, said an official from the cyber division.

Alimuzzaman, deputy commissioner of the division, said many mobile phone and computer users were becoming victims of cyber crimes mainly due to a lack of awareness about the offenses.

The number of such victims was increasing every year, he said, adding the main challenge in dealing with such cases and arresting the culprits was the delay in reporting to police.

He said many victims did not want to go to the law enforcers fearing that their identities would be revealed.

Referring to their analysis, the DC said in most of the cases, the accused spread defamatory and fake messages on online platforms and blogs using fake IDs and photos of the victims.

They also blackmail the victims after hacking their social media profiles, he said.

The offences also include email spoofing and spamming and spreading of propaganda and militancy-related contents, the analysis revealed.

Alimuzzaman said one percent of the 666 cases were related to terrorism, seven percent to blackmailing or extortion, 14 percent to pornography, 14 percent to financial frauds, 20 percent to hacking, 18 percent to defamation, 20 percent to fake IDs and six percent to other issues.

According to the database of the cyber security and crime division, the specialised unit arrested 67 suspects and submitted charge sheets against 24 last year.

Of the 666 complaints, the unit completed investigation of 233 last year. The others are under probe.

Although the division has 100 sanctioned posts, currently it has around 70 officials and other employees. To meet the growing challenge, the authorities have already proposed an organogram of 282 members.

Apart from the division, the Criminal Investigation Department (CID) and the Police Bureau of Investigation also have separate cyber crime units.