She was visiting a friend Sunday morning when someone broke into the house, Sgt. Darren Pearson said. The friend, identified as Carol Larese, 65, was badly wounded but was expected to recover.
Authorities arrested Leslie Williams, 31, when he crashed Welsh's car in Watertown after a police chase about five hours after the home invasion.
Williams has been charged with attempted murder, robbery, kidnapping with a firearm and other crimes connected with what happened to Larese, Pearson said. He said police were preparing to charge him in connection with crimes against Welsh. Williams was expected to be in court on Monday.
Pearson said it appears Williams acted alone in what he called a "crime of opportunity." Police said Welsh had been undergoing treatment for cancer and had a port in her chest.
Williams was released March 4 from the medium-security Osborne Correctional Institution in Somers after serving eight years in prison for convictions in 2000 of sexual assault and risk of injury to a minor, according to state Department of Correction records.
Brian Garnett, a correction spokesman, said Monday that Williams was disciplined twice in prison for making threats, once for violating provisions of a program there, and once for tampering with security.
He was denied parole in March 2006, and was placed on five years probation when he was released from prison, Garnett said.
According to the state sex offender registry, he lives in Hartford.
Cynthia Holland, a friend of the victims, said Monday that the two were having coffee when the home invasion happened.
"She's a lovely person," Holland said of Welsh.
Connecticut Governor Jodi Rell issued the following statement on the attack:
"Once more, all over Connecticut, decent people are reacting with horror and fury to a heinous, inexplicable and utterly reprehensible crime of violence. Understandably, the home invasion in New Britain on Sunday reawakens the shock and revulsion we felt after the crimes last summer in Cheshire and other such cases.
"I grieve for MaryEllen Welsh, who was brutally and senselessly killed while doing nothing more than visiting a friend for coffee, and my heart goes out to Carol Larese, who was wounded. Our thoughts and prayers are with both women, their families and their friends.
"As Governor of Connecticut, my resolve is ever stronger to deal sternly and forcefully with the vicious predators who would commit such outrages. We took real steps in January to strengthen our criminal justice systems - but the ghastly crimes in New Britain show us unequivocally that there is more to do and that there are some people who are so evil that ordinary measures will not stop them.
"First, I again call upon the General Assembly to pass legislation that will establish a clear and simple 'three strikes' law in Connecticut. The suspect in the New Britain case has a record that includes multiple burglaries and a sex offense involving a minor. He had been denied parole in 2006 and released on probation earlier this month after finishing an eight-year sentence.
"The time for excuses and rationalization has passed. We need a law that says if you commit three violent offenses, you will be sent to prison for the rest of your life. Period. It is time for action.
"Second, I am calling for legislation that will require any offender convicted of a second or subsequent sexual offense, regardless of the severity or degree, to face an automatic 50 percent increase in their sentence for that offense. No questions, no additional legal issues to prove in court, no unwieldy persistent offender statutes. Just an automatic 50 percent increase in sentence.
I am also asking the Chief State's Attorney, the Chief Justice of the Connecticut Supreme Court and the Commissioners of the Department of Public Safety and Department of Correction to attend a meeting in my office this week. The simple fact is this: We have laws already on the books - Megan's Law, Jessica's Law, persistent offender statutes and any other applicable laws - that are not being used in all cases. I want to know exactly what resources my Administration can provide that will ensure these laws are applied each and every time they can be. I also want to know what additional resources we can provide that will ensure that non-violent offenders and violent offenders who are unlikely to reoffend have the programs and services they need to remain on the straight and narrow.
"I will also be proposing that Pre-Sentence Investigations be mandatory in all cases involving sexual offenses. These full background checks of convicted criminals are sometimes waived. Yet it is clear one continuing problem we face is deciding which offenders are the most dangerous. The improvements we have made in Board of Pardons and Paroles operations are a start, but I believe it is absolutely essential that judges have the fullest picture possible of potentially dangerous offenders before they hand down a sentence that may not keep such a person in prison for the maximum period.
"Finally, I am calling on the Legislature to join me in restoring the funding for increased GPS monitoring of offenders on probation and parole - and to require GPS monitoring for all sexual offenders upon their release. I realize fully that this will have an impact on the budget - and yet I can think of no reason not to proceed.
"The crimes that took place on Sunday in New Britain offend us all. We must - and we will - react to these crimes in a resolute but measured way. The continuing, bipartisan effort to strengthen and enhance our criminal justice system is just such a reaction."
