The police probe has found involvement of 19 people in the killing of Taslima Begum Renu in the capital's Badda last year.

Investigation officer of the case, however, submitted charge sheet to a Dhaka court yesterday against 15 accused. The names of four other accused were not mentioned in the charge sheet as their "details could not be found during the investigation."

"Whenever we get the details of the four accused and will be able to arrest them, their names will also be included in the charge sheet," Detective Branch Inspector Abdul Haque, also the IO of the case, told The Daily Star yesterday.

Of the 15 charge-sheeted accused, 14 are already arrested while one is on the run. Three of the arrestees have made confessional statements. The accused are either vendors of a local Bazar or pedestrians, the IO added.

On July 20 last year, 40-year old Taslima, a single mother of four-and-a-half-year-old Tuba and Ta-seen al Mahir, a fifth-grader, had gone to Badda Uttar-Purba Primary School to inquire about admission in hopes of getting Tuba enrolled.

But a mob beat her brutally to death in front of the school gate, suspecting her to be a child kidnapper. Videos taken on mobile phones and CCTV, which later went viral, showed some young people kicking, striking, and trampling Taslima amid a gathering of several hundred people, most of whom were just silent spectators.

The killing, which touched off a firestorm of outrage in the country, took place at a time when incidents of mob attacks on people labelling them as "child kidnappers" were on the rise.

Such incidents went up following rumours on "human sacrifice" at the construction site of Padma bridge.

Following the incident, Syed Nasir Uddin Titu, a nephew of Taslima, filed the case against 400 to 500 unknown attackers with Badda Police Station.

At least eight people were killed while a couple of dozen others were injured in mob beatings at different places across the country in July last year.

Asked about the motive of Taslima murder, Inspector Abdul Haque said a vested quarter tried to destabilise law and order spreading the rumour.

"Taslima is a victim of an ill-effort and provocation," he told The Daily Star. Asked whether they found involvement of the headteacher of Badda Uttar-Purba Primary School as alleged by the complainant of the case on several occasions, the IO said he did not get any involvement of the headmaster.

Rather, the headmaster tried to save the victim shutting the collapsible gate of the school.

Syed Nasir Uddin Titu yesterday said many other people were involved in the killing and they wanted more attackers' names to be included in the charge sheet.

"Now we want the judgment to carry a message that helps create a rumour-free Bangladesh for the new generation," he added.